JP2008293861A - Light emitting device array and lighting device - Google Patents

Abstract

Provided are a light emitting device array and an illuminating device that do not cause nonuniformity in light emission intensity between light emitting device arrays due to a failure occurring in a part of the light emitting device array.
A light emitting device array in which a plurality of LEDs (121, 122) are driven by power supplied from a constant current source (110), and the same number of LEDs (121, 122) are electrically connected in series to form I (Vf). ) LED array 131 and I (Vf) LED array 132 are formed. The LED array 131 and the LED array 132 are respectively connected to the positive electrode 111 and the negative electrode provided outside the light emitting device array 100. The electrode 112 is electrically connected in parallel, and the positive electrode 111 and the negative electrode 112 are electrically connected to the constant current source 110.
[Selection] Figure 1

Description

  The present invention relates to a light-emitting device that hardly causes unevenness in light emission intensity, and a light-emitting device array and lighting device using the same, and in particular, a light-emitting device that constitutes LED lighting and LED backlight devices using LEDs as light sources. The present invention relates to a light-emitting device array and a lighting device that hardly cause a change in light emission intensity even when a problem occurs in part and a part of a power supply path is disconnected.

  2. Description of the Related Art Conventionally, illuminations, backlights for liquid crystal screens, and the like are configured to emit light by emitting light with a light-emitting device called a light-emitting device array composed of one light-emitting device or a plurality of light-emitting devices.

  In recent years, electronic devices such as LEDs and organic light emitting diodes (OLEDs) have been used as light emitting elements used in these light emitting devices or light emitting device arrays in place of fluorescent lamps and FL tubes. The amount of voltage drop per unit is small. Therefore, when a plurality of light emitting devices are used, they are electrically connected in series in order to make the power supply voltage compatible with conventional light emitting elements.

  Here, a configuration for operating the conventional light emitting device will be described with reference to FIGS.

  In FIG. 11, a plurality of light emitting devices 820 each having one LED 821 mounted in a package are connected in series to form a light emitting device row 831, and the light emitting device rows are combined to form a light emitting device. 2 is a block diagram of a device array 800. FIG. The light emitting device array 800 is electrically connected to the positive electrode and the negative electrode.

  FIG. 12 shows an example of a light-emitting device array 900 formed by a light-emitting device 920 on which a plurality of (two in FIG. 12) LEDs 921 are mounted in a package. In the light emitting device array 900 shown in FIG. 12, each LED 921 is connected in series with a plurality of LEDs 921 mounted on other light emitting devices to form a light emitting device row 931, and a plurality of light emitting devices are combined as a whole. Shows the configuration.

  When a light-emitting device array is formed using a plurality of light-emitting elements (here, LEDs) as shown in FIG. 11 or FIG. 12, it is necessary to align the light emission intensities of the individual light-emitting elements in order to make the light-emitting device array emit light uniformly. is there.

  FIG. 13 is a graph showing a relationship (IL characteristic) between the forward current and emission intensity of a general LED, and FIG. 14 is a relationship (V-I characteristic) between the forward voltage and forward current of the LED. ). In this specification, “forward voltage” means a potential with respect to the cathode of the anode of the LED. The vertical axis in FIG. 13 is labeled as relative luminous intensity, but the luminous intensity is the intensity per unit solid angle and is the same as the relative intensity because it is measured at the same solid angle.

  As shown in FIG. 13, the LED has a characteristic that the light emission intensity is substantially proportional to the forward current applied. For this reason, in order to make each light-emitting device emit light with uniform intensity, the currents flowing through the light-emitting devices may be made the same.

  It is known that an LED has a variation in VI characteristics depending on its manufacturing process. FIG. 14 shows the VI characteristics of a chip VF1 having a large forward current (I (Vf)) and a small chip VF2 with respect to the same forward voltage. In LED, such a difference in VI characteristics between elements is inevitable. Since it is difficult to use a large number of LEDs having different V-I characteristics and to uniformize the relationship (IL characteristics) between the light emission intensity and the forward current of each light-emitting device array, it is usually the predetermined forward direction of the LEDs. The LEDs are selected such that the forward current I (Vf) at the voltage Vf falls within a certain range, and the light emitting device array and the light emitting device array are configured. Further, in order to make the intensity of the current flowing to the LED constant and make the light emission intensity uniform, the power supply device is generally composed of a constant current power supply circuit. By comprising in this way, it can comprise so that each light-emitting device row | line | column comprised with a some light-emitting device may perform uniform light emission (light irradiation).

  In the light emitting device array, the light emitting device rows in which many light emitting devices are connected in series as described above are configured to emit light uniformly. However, since the light emitting device row has a portion in which the light emitting devices are connected in series, when a failure occurs in any of the light emitting devices connected in series, the light emission intensity of the corresponding light emitting device row is reduced, There has been a problem that non-uniformity occurs in the intensity of the light emitting device array.

  A malfunction occurring in the light emitting device is, for example, an open failure. An open failure is a failure in which an electrical path is disconnected. Describing based on the cross-sectional views of the light-emitting device 950 shown in FIGS. 15 to 18, a light-emitting element provided on a substrate 951 and electrically connected by a wire 952 made of a thin gold wire or the like of about several μm to several tens of μm. In the case of (LED953), the above-mentioned wire 952 is disconnected (FIG. 16) or the LED953 is peeled off from the substrate and electrically disconnected (FIG. 17) is an open failure.

  Japanese Patent Application Laid-Open No. 2004-228688 discloses a technique for causing an influence of a part of a light emitting device array to be contained when a problem occurs in a part of the light emitting devices that are electrically connected in series.

FIG. 18 is a circuit diagram illustrating a state in which a plurality of light emitting devices configured by the method of Patent Document 1 form a light emitting device array. In the method of Patent Document 1, even if any of the light emitting devices forming the light emitting device array has an open failure, a voltage almost the same as the voltage acting on the normal light emitting device is supplied by a resistor incorporated in the circuit. The technology that can maintain the light emission intensity as a whole of the light emitting device array is disclosed.
JP 2003-100109 A (published April 4, 2003)

  However, the above-described conventional configuration has a problem in that the light emission intensity between the light emitting device columns is uneven due to a failure occurring in a part of the light emitting device array in which a plurality of light emitting devices are combined.

  As described above, in the light emitting device array according to the prior art, each light emitting device is configured to emit and emit substantially the same light. For this reason, when a failure occurs in the light emitting device, the light in the place that the light emitting device takes over is lost as it is.

  Further, in the method shown in Patent Document 1, since a path for passing current is formed around the failed light emitting device, it is possible to avoid a situation in which a large number of light emitting devices do not emit light due to failure of some light emitting devices. Although it is possible, the failed light emitting device itself is turned off, and the light emission intensity among the light emitting devices is not uniform. Although the current path that bypasses the failed light emitting device is guaranteed, the amount of current consumed by the entire light emitting device array does not change, so the light emitting device is near the bypassed current path. It is inevitable that the emission intensity changes between the two.

  The present invention has been made in view of the above-described conventional problems, and an object of the present invention is to cause nonuniformity in the light emission intensity between the light emitting device columns and in the light emitting device array due to a failure occurring in some light emitting devices. It is an object to provide a light emitting device array and a lighting device that are free from problems.

  In order to solve the above-described problem, the light-emitting device array of the present invention includes at least one or more power supply lines, a plurality of power supply lines connected in parallel thereto, and a plurality of power supply lines. In a light-emitting device array configured by connecting light-emitting devices in series, each light-emitting device has a light-emitting diode that mainly emits light, and mainly due to a difference in forward current with respect to the same forward voltage during initial driving. A predetermined number of secondary light emitting diodes each having a light emission intensity smaller than that of the light emitting diodes are included, and each light emitting diode has an independent pair of terminals corresponding to each light emitting diode. The lines are connected to different power supply lines so as to have the same forward current-light emission characteristics.

  According to the above configuration, the light emitting device is connected in series so as to extend over the power supply line, and the light emitting device includes a light emitting diode that mainly emits light and a light emitting that emits secondary light having a smaller light emission intensity. Each light emitting diode is connected to a separate power supply line so as to have the same I (Vf) -light emission characteristic in each current supply line. Therefore, a larger amount of current flows through the power supply line to which the light emitting diodes that emit light mainly are connected than to the power supply line to which the light emitting diodes that emit light from the secondary side are connected.

  Here, when a disconnection occurs in one of the power supply lines, the constant current power supply unit supplies all power to the power supply line that is not disconnected. In addition, since the constant current power supply unit supplies power so as to maintain the same current value that was supplied at the time of initial driving, the current value consumed by the light emitting device array is the same regardless of whether there is a disconnection or not. It is constant. In the light emitting diode, the magnitude of the forward current and the light emission intensity are proportional to each other. Therefore, the light emitting device array maintains a constant light emission intensity regardless of the presence or absence of disconnection. Therefore, there is an effect that it is possible to provide a light emitting device array that does not cause nonuniformity in light emission intensity between the light emitting device arrays due to a failure occurring in a part of the light emitting device array.

  Moreover, the structure by which a current limiting means is connected only to the electric power supply line to which the light emitting diode made to light-emission is connected may be sufficient.

  In addition, current limiting means is connected to each power supply line, so that the current limit of the power supply line connected to the light emitting diode that emits light secondary is larger than the light emitting diode that emits light mainly. It may be a configured.

  According to the above configuration, since the voltage drop occurs in the power supply line to which the light emitting diode that emits secondary light is connected, the current value of the power supply line is limited. Therefore, the light emitting diode that mainly emits light emits light more strongly than the light emitting diode that emits light secondarily.

  In addition, according to the above configuration, the current limiting unit in the power supply line to which the light emitting diode that emits secondary light is connected is more than the current limiting unit in the power supply line to which the light emitting diode that mainly emits light is connected. However, the current limit is large. Therefore, since the voltage drop is larger in the power supply line connected to the light emitting diodes that emit light from the side, the light emitting diodes that emit light mainly emit light more strongly than the light emitting diodes that emit light from the side.

  On the other hand, when a disconnection occurs in one of the power supply lines, the constant current power supply unit supplies all power to the power supply line that is not disconnected. In addition, since the constant current power supply unit supplies power so as to maintain the same current value that was supplied at the time of initial driving, the current value consumed by the light emitting device array is the same regardless of whether there is a disconnection or not. It is constant. In the light emitting diode, the magnitude of the forward current and the light emission intensity are proportional to each other. Therefore, the light emitting device array maintains a constant light emission intensity regardless of the presence or absence of disconnection.

  In order to solve the above problems, the light emitting device array of the present invention has at least one light emitting device in series by one constant current power supply unit, one power supply line connected in parallel thereto, and the power supply line. In the connected light emitting device array, each light emitting device has a secondary light emitting intensity smaller than that of the light emitting diode that mainly emits light and the diode that mainly emits light due to the difference in the number of light emitting diodes in the initial driving. A predetermined number of light emitting diodes that emit light is included, and each light emitting diode is connected in parallel in the light emitting device, and is collectively connected to a pair of terminals provided in the light emitting device connected to the power supply line. It is characterized by having.

  According to the above configuration, since each light emitting diode is connected in parallel in the light emitting device, even if a disconnection occurs in one of the light emitting diodes, the constant current power supply unit does not cause a disconnection. To supply all power. That is, the constant current power supply unit supplies power so as to maintain the same current as that supplied at the time of initial driving. Therefore, the current value in each light emitting device is constant regardless of the presence or absence of disconnection. In the light emitting diode, the magnitude of the forward current and the light emission intensity are proportional to each other, so that each light emitting device maintains a constant light emission intensity regardless of the presence or absence of disconnection. Therefore, there is an effect that it is possible to provide a light emitting device array that does not cause nonuniformity in light emission intensity between the light emitting device arrays due to a failure occurring in a part of the light emitting device array.

  Moreover, the structure by which the current limiting means was connected only to the diode which light-emits secondary in a light-emitting device may be sufficient.

  In addition, the diode that mainly emits light may have a configuration in which the forward current with respect to the same forward voltage is larger than the diode that emits light secondarily.

  According to the above configuration, the current limiting means limits the current value of the light emitting diode because a voltage drop occurs in the light emitting diode that emits light secondarily. Therefore, the light emitting diode that mainly emits light emits light more strongly than the light emitting diode that emits light secondarily.

  In addition, according to the above configuration, the current limiting unit in the light emitting diode that emits light secondarily has a larger current limit than the current limiting unit in the light emitting diode that emits light mainly. Accordingly, since the voltage drop of the light emitting diode that emits light secondarily is larger, the light emitting diode that emits light mainly emits light stronger than the light emitting diode that emits light secondarily.

  On the other hand, when a disconnection occurs in one of the light emitting diodes, the constant current power supply unit supplies all power to the light emitting diodes that are not disconnected. In addition, since the constant current power supply unit supplies power so as to maintain the same current value as that supplied at the time of initial driving, the current value consumed by each light-emitting device does not depend on whether or not there is a disconnection. It is constant. In the light emitting diode, the magnitude of the forward current and the light emission intensity are proportional to each other, so that each light emitting device maintains a constant light emission intensity regardless of the presence or absence of disconnection.

  The current limiting unit may be a resistor.

  In order to solve the above problems, the light-emitting device array of the present invention has one constant current power supply unit, a plurality of power supply lines connected in parallel thereto, and a plurality of identical forward currents for each power supply line. In a light-emitting device array provided with a light-emitting device having a light-emitting diode array in which light-emitting diodes having light-emitting characteristics are connected in series, the light-emitting diode column includes a light-emitting diode column that mainly emits light and a sub-light intensity that is smaller than that. There is a light emitting diode row that emits light next, and the number of light emitting diodes included in the secondary light emitting diode row is connected more than the light emitting diode row that mainly emits light. .

  According to the above configuration, since the number of light emitting diodes included in the array of light emitting diodes that emit light secondarily is larger than the number of light emitting diode arrays that emit light mainly, light emission that emits light in a secondary manner is performed. The voltage applied to the diode is smaller than the voltage applied to the light emitting diode that mainly emits light. Therefore, the light emitting diode array that emits light mainly emits light more strongly because a larger amount of current flows.

  Here, when a disconnection occurs in one of the power supply lines, the constant current power supply unit supplies all power to the power supply line that is not disconnected. In addition, since the constant current power supply unit supplies power so as to maintain the same current value that was supplied at the time of initial driving, the current value consumed by the light emitting device array is the same regardless of whether there is a disconnection or not. It is constant.

  Since disconnection is likely to occur in a light emitting diode through which a large amount of current flows, disconnection is more likely to occur in a light emitting diode row that emits light mainly. When the disconnection occurs in the light emitting diode row that emits light mainly, the constant current power supply unit supplies all the power to the light emitting diode row that emits light secondary. That is, since the current is redistributed to the light emitting diode rows connected to a large number of light emitting diodes, the current is redistributed to more light emitting diodes than the light emitting diodes connected to the light emitting diode rows that are disconnected. Current is supplied. Accordingly, since the light emitting device array emits light more strongly than before the disconnection occurs, it is possible to ensure the light emission intensity required at the time of use and notify the user that a disconnection has occurred in any of the light emitting diodes.

  The light emitting diode may be configured by a bullet-shaped light emitting diode element.

  The light emitting diode may be configured by a light emitting diode element having a shape mounted on the surface of the substrate.

  In order to solve the above problems, the illumination device of the present invention is characterized by using the above light emitting device array as a light source.

  In order to solve the above-described problems, the illumination device of the present invention is characterized in that the light-emitting device array is used as a light source of a backlight.

  According to said structure, the illuminating device which does not produce nonuniformity in the emitted light intensity between light emitting device arrays by the failure which arose in a part of light emitting device array can be provided.

  As described above, the light-emitting device array of the present invention includes at least one light-emitting device so as to span one constant current power supply unit, a plurality of power supply lines connected in parallel thereto, and a plurality of power supply lines. In the light-emitting device array configured to be connected in series, each light-emitting device includes a light-emitting diode that mainly emits light and a diode that mainly emits light due to a difference in forward current with respect to the same forward voltage during initial driving. A predetermined number of secondary light emitting diodes having a light emission intensity smaller than that are included, each having an independent pair of terminals corresponding to each light emitting diode, and each light emitting diode at each current supply line, It is connected to different power supply lines so as to have the same forward current-luminescence characteristics.

  Further, as described above, in the light emitting device array of the present invention, at least one light emitting device is connected in series by one constant current power supply unit, one power supply line connected in parallel thereto, and the power supply line. In the light emitting device array configured as described above, each light emitting device has a secondary light emitting intensity smaller than that of a light emitting diode that emits light mainly and a diode that emits light mainly due to the difference in the number of light emitting diodes during initial driving. A predetermined number of light emitting diodes are included in each of the light emitting diodes, and each light emitting diode is connected in parallel in the light emitting device, and is collectively connected to a pair of terminals provided in the light emitting device connected to the power supply line. Yes.

  In addition, as described above, the light emitting device array of the present invention includes one constant current power supply unit, a plurality of power supply lines connected in parallel thereto, and a plurality of the same forward current-light emission for each power supply line. In a light emitting device array provided with a light emitting device having a light emitting diode row in which light emitting diodes having characteristics are connected in series, the light emitting diode row mainly includes a light emitting diode row to emit light and a secondary light emitting intensity smaller than that. There are light emitting diode rows that emit light, and the light emitting diode rows that emit light mainly are connected to a larger number of light emitting diodes than the light emitting diode rows that emit light secondary.

  Moreover, the illumination device of the present invention uses the light emitting device array as a light source as described above.

  In the illumination device of the present invention, as described above, the light emitting device array is used as a light source of a backlight.

  Therefore, there is an effect that it is possible to provide a light emitting device array and an illuminating device that do not cause nonuniformity in light emission intensity between the light emitting device arrays due to a failure occurring in a part of the light emitting device array.

  Embodiments of the present invention will be described with reference to FIGS.

  FIG. 1 is a block diagram showing a light emitting device array of the present embodiment.

  In the light emitting device array 100 in this embodiment, light emitting devices 120 each having two light emitting elements connected to different light emitting device columns are connected in series and connected to a constant current source 110. ing. The constant current source 110 is a power source that can always apply a constant current to the light emitting device array 100, and includes a positive electrode 111 and a negative electrode 112. A known constant current device or the like can be used as the constant current source 110 of the present embodiment.

  The two LEDs included in the light emitting device 120 include two LEDs 121 and LEDs 122 having different forward currents even when the forward voltage Vf is the same. In this embodiment, in order to facilitate understanding of the description, the forward current when the forward voltage is Vf is denoted as I (Vf). In FIG. 1, the size of the diode schematically represents the size of I (Vf) with respect to a predetermined Vf. When I (Vf) of the LED 121 is I (Vf) 1 and I (Vf) of the LED 122 is I (Vf) 2, the case of I (Vf) 1 ≠ I (Vf) 2 is always described. Even if two or more LEDs are included in one light-emitting device, and most of the LEDs have the same I (Vf) and some of the LEDs have different I (Vf), the light-emitting device of the present embodiment Can be configured.

  The anode terminals of the LED 121 and the LED 122 are electrically connected to the positive electrode 111 side of the constant current source 110, and the cathode terminals are electrically connected to the negative electrode 112 side of the constant current source 110. Moreover, the anode terminal of each LED may be connected to the constant current source 110 as a positive electrode, and the cathode terminal of each LED may be connected to the constant current source 110 as a negative electrode.

  As the LEDs 121 and 122, well-known LEDs can be used. Further, the light emitting device may be constituted by a bullet-shaped light emitting diode device, or may be constituted by a light emitting diode device shaped to be mounted on the substrate surface.

  When the light emitting devices 120 are connected in series, the cathode terminal of the LED 121 and the anode terminal of the next LED 121 are connected, and the cathode terminal of the LED 122 and the anode terminal of the next LED 122 are connected. An LED array formed by a plurality of LEDs 121 is referred to as an LED array 131. An LED array formed by the plurality of LEDs 122 is referred to as an LED array 132. In this embodiment, the case where two LEDs are arranged is described, but the number of LEDs provided in the light emitting device 120 is not limited to the above, and may be set according to the light emission intensity required by the light emitting device 120. Good.

  In the light emitting device array 100 of the present embodiment, since the light emitting devices 120 are connected in series as described above, the number of LEDs constituting each of the LED rows 131 and the LED rows 132 connected in series is equal.

  In the present embodiment, the magnitudes of I (Vf) of the LEDs 121 mounted on the respective light emitting devices 120 are equal to I (Vf) 1, and the magnitudes of I (Vf) of the LEDs 122 are equal to I (Vf). 2 is assumed. Further, it is assumed that the magnitude of I (Vf) of the LED 121 is smaller than the magnitude of I (Vf) of the LED 122.

  As a result, the size of I (Vf) of the LED 121 and the LED 122 may be configured as described above. For example, a large number of LEDs may be selected as described above according to the size of I (Vf). Alternatively, it may be intentionally manufactured so as to have I (Vf) as described above.

  In general, the IV characteristic of the LED is as shown in FIG. 14, but when a current larger than a certain forward current, for example, 1 mA, starts to flow, light emission becomes visible.

  FIG. 2 shows the IV characteristics of the LED of the present embodiment. When a predetermined current, for example, 10 mA is supplied to the LED, it can be seen that Vf is about 3.5 V in the LED 122, whereas Vf is about 3.0 V in the LED 121.

  First, when the light emitting device row constituting the light emitting device array 100 is composed of one light emitting device, that is, when the LED 121 and the LED 122 provided in the light emitting device 120 are electrically connected in parallel. Will be described.

  FIG. 3 is a block diagram illustrating a state in which the light emitting device 120 according to the present embodiment includes one LED 121 and one LED 122.

  In the light emitting device 120, the LED 121 and the LED 122 are electrically connected in parallel. Therefore, when the light emitting device 120 is connected to the constant current source 110 as shown in FIG. 3, the same voltage is applied to the LED 121 and the LED 122 that are electrically connected in parallel.

  As described above, since the LED 121 has a larger I (Vf) than the LED 122 at the same forward voltage Vf, from FIG. 2, when the same voltage acts on the LED 121 and the LED 122, the LED 121 flows more current than the LED 122. I understand that. For example, when a voltage of 3.5 V is applied to the light emitting device 120 of this embodiment, it can be seen that a current of about 20 mA flows through the LED 121 and a current of about 10 mA flows through the LED 122.

  In the light emitting device array 100 of the present embodiment, the power source that supplies power to the light emitting device 120 is the constant current source 110. The constant current source 110 operates so that a constant current flows through the light emitting device 120. That is, in the light emitting device array 100 according to the present embodiment, first, the current to be applied to the light emitting device 120 is determined by the constant current source 110. In the light emitting device 120, the currents flowing through the respective LEDs 121 and 122 are determined so that the sum of the currents flowing through the LEDs 121 and 122 is equal to the current flowing through the constant current source 110 and the potential differences applied to both ends of the LEDs 121 and 122 are equal. .

  That is, when the constant current source 110 supplies a current of 30 mA, the total value of the currents flowing through the LED 121 and the LED 122 is 30 mA, and the potential difference applied to both ends of the LED 121 and the LED 122 is equal. Specifically, a current of about 20 mA flows through the LED 121, a current of about 10 mA flows through the LED 122, and a potential difference applied to both ends of each LED becomes 3.5V.

  In the above, the case where the light emitting device row is configured by one light emitting device 120 has been described. When a plurality of such light emitting devices 120 are electrically connected in series, the magnitude of the current acting on the LEDs 121 or LEDs 122 connected in series is such that the light emitting device array is composed of one light emitting device 120. The same amount of current flows as if Therefore, the potential difference applied to both ends of the LED array 131 and the LED array 132 is equal, and about 20 mA flows through the LED array 131 and about 10 mA flows through the LED array 132.

  In the light emitting device array 100 of the present embodiment, the forward current flowing through the LEDs 121 provided in the light emitting device 120 is larger than the forward current flowing through the LEDs 122.

  As described above, when a current of 30 mA is supplied to the entire light emitting device array 100 of the present embodiment, a current of about 20 mA flows through each LED 121 and a current of about 10 mA flows through each LED 122. That is, the LED 121 emits light with an intensity about twice that of the LED 122 due to the relationship between the forward current and the light emission intensity shown in FIG.

  That is, the light emitted from the LEDs 121 occupies most of the light emitted from the light emitting device 120, while the light emitted from each of the LEDs 122 becomes auxiliary light.

  A device that consumes power, such as a light-emitting device, is susceptible to thermal shock (thermal stress) due to heat generated by power consumption. In particular, the greater the power consumed, the higher the rate of thermal shock, which causes open failures due to disconnection of the LED wiring or peeling of the LED from the substrate as in the conventional case.

  Even in the light emitting device array 100 of the present embodiment, it is conceivable that the influence of thermal shock accompanying power consumption is affected to the same extent as in the conventional light emitting device array. In the light emitting device array 100 of the present embodiment, a large amount of current flows through the LEDs 121 provided in the light emitting device 120 as described above, and it is considered that the LEDs 121 are more susceptible to thermal shock than the LEDs 122.

  For example, if the LED 121 provided in any of the light emitting devices 120 is disconnected due to the influence of thermal shock or the like, no current flows through the LED array 131 connected in series to the disconnected LED 121.

  At this time, in the light emitting device array 100 according to the present embodiment, power is supplied to the plurality of light emitting devices 120 connected in series by the constant current source 110, so the constant current source 110 is not related to the disconnection of the LED 121. A constant current is continuously supplied to the plurality of light emitting devices 120 connected in series.

  Specifically, when the constant current source 110 is set to pass a current of 30 mA through the light emitting device array 100 of the present embodiment, the LED array in the light emitting device array 100 of the present embodiment is as described above. A current of about 20 mA flows through 131, and a current of about 10 mA flows through the LED array 132. A voltage of 3.5 V acts on each LED 121 and each LED 122.

  Here, even when one of the LEDs 121 is disconnected and no current flows through a circuit in which the LED array 131 is connected in series among the plurality of light emitting devices 120, the constant current source 110 is 30 mA in the light emitting device array 100. Keep current flowing.

  That is, in this case, a current of 30 mA flows through the LED array 132. A current of 30 mA flows through each LED 122.

  In the LED, the light emission intensity is determined in proportion to the magnitude of the forward current flowing as shown in FIG. Therefore, in the light emitting device array 100 of the present embodiment, the light emission intensity generated before the LED 121 is disconnected is maintained.

  In the above description, the case where the LED 121 with high emission intensity is disconnected is described. However, when the LED 122 with low emission intensity is disconnected, a current of 30 mA flows through the LED 121 in the same manner, and the emission intensity generated before the LED 122 is disconnected. Is preserved.

  By using the light emitting device array as described above, any of the LEDs has a problem, and even if a part of the power supply path is disconnected, the lighting device and the backlight device that hardly change the light emission intensity. Can be configured.

  In addition, although the case where I (Vf) of the plurality of LEDs provided in the light emitting device 120 has a different configuration has been described above, it is configured by a plurality of LEDs having the same I (Vf) as shown in FIG. It is also possible.

  FIG. 4 is a block diagram showing another light emitting device array 200 of the present embodiment.

  In the light emitting device array 200, as in the light emitting device array 100, the light emitting devices 220 are connected in series and are connected to the constant current source 210.

  The light emitting device 220 includes an LED 221 and an LED 222 having the same I (Vf). The LED 221 and the LED 222 form an LED array 231 and an LED array 232 in the same manner as the LED 121 and LED 122, and the anode terminal of the LED array 231 is electrically connected to the positive electrode 211 side of the constant current source 210. The cathode terminal is electrically connected to the negative electrode 212 side of the constant current source 210 described above.

  On the other hand, the anode terminal of the LED string 232 is electrically connected to one terminal of the current limiting resistor 213, and the other terminal of the current limiting resistor 213 is electrically connected to the positive electrode 211 side of the constant current source 210. Connected. The cathode terminal of the LED array 232 is electrically connected to the negative electrode 212 side of the constant current source 210.

  That is, in the LED strings 232, the current limiting resistors 213 are electrically connected in series, and a voltage drop occurs in the current limiting resistors 213 due to the current flowing through the LED strings 232. It is limited to be smaller than the LED 221. That is, the current flowing through each LED 222 is smaller than the current flowing through the LED 221.

  For example, when five light emitting devices 220 are connected in series, the electrical characteristics of the respective LEDs 221 and 222 are equal to the LED 121, and the resistance value of the current limiting resistor 213 is 250 ohms, the constant current source 210 , Based on a specific example of supplying a current of 30 mA, a current of 20 mA flows through the LED array 231 and a current of 10 mA flows through the LED array 232.

  At this time, a voltage of 3.5 V × 5 = 17.5 V is applied to the LED array 231, a voltage of 3 V × 5 = 15 V is applied to the LED array 232, and 250Ω × is applied to the current limiting resistor 213. A voltage of 10 mA = 2.5V is applied. That is, the amount of voltage drop generated in the LED array 231 is equal to the amount of voltage drop generated by the LED array 232 and the current limiting resistor 213, and the total current flowing through the LED array 231 and the LED array 232 is equal to the constant current source 210. It is equal to the supplied current value.

  At this time, since each LED 221 in the LED row 231 has a current twice as large as the current flowing in each LED 222 in the LED row 232, each LED 221 emits light with an intensity about twice that of the LED 222. Will do.

  That is, in this case, each of the LEDs 221 forms a main component of light emitted from the light emitting device 220 and forms a main component of light emitted from the light emitting device array 200. On the other hand, each of the LEDs 222 is configured to emit light supplementarily.

  Since the current flowing through the LED 221 is twice as large as the current flowing through the LED 222 as described above, the rate of thermal shock is high as described above. It is thought that it is easy to cause an open failure due to peeling of the skin.

  When any LED 221 constituting the LED array 231 is disconnected, the current 30 mA supplied from the constant current source 210 flows to the LED array 232 and the current limiting resistor 213 in the same manner as the light emitting device array 100 described above. Become.

  That is, even in the light emitting device array 200 of the present embodiment, the light emission intensity generated before the LED 221 is disconnected is maintained.

  As shown in FIG. 5, a current limiting resistor 214 is inserted in series with the LED array 231, and the LED array 231 and the LED array 232 depend on the resistance values of the current limiting resistor 213 and the current limiting resistor 214. The emission intensity of the light may be adjusted.

  In the above description, the case where the light emitting device array is a parallel connection of a plurality of LED rows is described. However, like the light emitting device 300 and the light emitting device 400 shown in FIGS. 4 may be formed by one LED instead of the LED row described in FIG.

  FIG. 6 shows a light-emitting device 300 in which one LED 121 and one LED 122 are electrically connected in parallel, and FIG. 7 shows a current limiting device that is electrically connected in series to the LED 221, LED 222, and LED 222. A light-emitting device 400 in which a pair of resistors 213 are electrically connected in parallel is described.

  Moreover, the light-emitting device array 500 or 600 as shown in FIGS. 8 and 9 in which the light-emitting devices described in FIGS. 6 and 7 are connected in series can also be configured.

  In the light emitting devices 300 and 400 and the light emitting device arrays 500 and 600 shown in FIGS. 6 to 9, even when any LED stops emitting light due to disconnection or the like, a current flows through the LEDs connected in parallel. Since the currents flowing through the light emitting devices 300 and 400 do not change, the light emission intensity of the light emitting devices 300 and 400 does not change.

  Further, as in a light emitting device array 700 shown in FIG. 10, the number of LEDs forming each LED row may be different.

  FIG. 10 is a block diagram showing another light emitting device array 700 of the present embodiment.

  In the light emitting device array 700, the number of LEDs 721 and 722 forming the LED row 731 and the LED row 732 is different. In the light-emitting device array 700 illustrated in FIG. 10, the electrical characteristics of the LEDs 721 and the LEDs 722 constituting the LED array 731 and the LED array 732 are equal, and the LED array 732 is configured rather than the number of the LEDs 721 configuring the LED array 731. The case where the number of LEDs 722 is larger is shown.

  The LED array 731 and the LED array 732 are electrically connected in parallel, and are electrically connected to the constant current source 710. Therefore, the voltages applied to the LED array 731 and the LED array 732 are equal.

  On the other hand, in the LED row 732, more LEDs are connected in series than the LED row 731. Therefore, the voltage drop that occurs in each of the LEDs 722 that make up the LED string 732 is smaller than the voltage drop that occurs in each of the LEDs 721 that make up the LED string 731.

  For example, when the LED array 731 is formed by electrically connecting four LEDs 721 in series, and the LED array 732 is formed by electrically connecting five LEDs 722 in series, a constant current source When 710 supplies a current of 30 mA, a current of about 22 mA flows through the LED array 731 and a current of about 8 mA flows through the LED array 732.

  At this time, a voltage of about 3.6 V × 4 = about 14.4 V is applied to the LED array 731, and a voltage of about 2.9 V × 5 = about 14.5 V is applied to the LED array 732. That is, the amount of voltage drop generated in the LED array 731 is equal to the amount of voltage drop generated by the LED array 732, and the total current flowing through the LED array 731 and the LED array 732 is equal to the current value supplied by the constant current source 710. It has become.

  At this time, since each LED 721 of the LED array 731 has a current approximately 2.75 times as large as the current flowing through each LED 722 of the LED array 732, each LED 721 is approximately 2.75 times of the respective LED 722. It emits light with double the intensity. When the light emission intensity of one LED 722 is L, the light emission intensity of the LED array 732 is 5L, the light emission intensity of the LED array 731 is 2.75L × 4 = 11L, and the light emission intensity of the light emitting device array 700 is 5L + 11L = 16L.

  That is, in this case, each of the LEDs 721 forms a main component of light emitted from the light emitting device array 700. On the other hand, each of the LEDs 722 is configured to emit light supplementarily.

  Since the current flowing through the LED 721 is about 2.75 times as large as the current flowing through the LED 722 in this way, the rate of thermal shock as described above is high. This is considered to cause an open failure due to peeling from the substrate.

  When any of the LEDs 721 constituting the LED row 731 is disconnected, the current 30 mA supplied from the constant current source 710 flows to the LED row 732 as in the light emitting device array 100 described above.

  In this case, since the current of about 3.75 times before the LED 721 is disconnected flows through the LED 722, the light emission intensity is about 3.75 times before the LED 721 is disconnected.

  The light emission intensity of the light emitting device array 700 at this time is 3.75L × 5 = 18.75L, where L is the light emission intensity of the LED 722 before the LED 721 is disconnected, and is larger than the light emission intensity before the LED 721 is disconnected. . That is, by exceeding the light emission intensity before the LED 721 is disconnected, the light emission intensity required when using the light emitting device array 700 is secured and the user is notified that any of the LEDs is disconnected. it can.

  In order to solve the above problems, a light-emitting device array of the present invention is a light-emitting device array in which a plurality of light-emitting diodes are driven by power supplied from a constant current power supply unit. A plurality of light emitting diode rows formed in series with each other to form a first light emitting diode row and a second light emitting diode row made of LEDs having an I (Vf) smaller than the first light emitting diode row. The first light emitting diode array and the second light emitting diode array are each electrically connected in parallel to a terminal provided outside the light emitting device, and the terminal is electrically connected to the constant current power supply unit. It is characterized by being connected.

  According to the above configuration, when a plurality of light emitting diode arrays having different I (Vf) characteristics are electrically connected to the constant current power supply unit in parallel, the light emitting diode array composed of light emitting diodes having a large I (Vf) is used. More current flows than a light-emitting diode array composed of light-emitting diodes having a small I (Vf).

  In the light emitting diode, since the light emission intensity increases in proportion to the magnitude of the forward current, the light emitting diode of the present light emitting device is composed of a light emitting diode having a large I (Vf) by the power supplied from the constant current power supply unit. The column emits light more strongly than the light-emitting diode column composed of light-emitting diodes having a small I (Vf).

  On the other hand, when a disconnection occurs in any of the light emitting diode rows, the constant current power supply unit supplies all the power to the light emitting diode rows that are not disconnected. The constant current power supply unit supplies power so as to maintain the same current as the current value supplied before any light emitting diode is disconnected. Therefore, the current value consumed by the light emitting device array is a constant value regardless of the disconnection of the light emitting diode.

  Therefore, in this light emitting device array, a constant light emission intensity can be maintained regardless of the disconnection of the light emitting diode.

  In order to solve the above problems, a light-emitting device array of the present invention is a light-emitting device array in which a plurality of light-emitting diodes are driven by power supplied from a constant current power supply unit. A third light emitting diode row in which the first resistance means is electrically connected in series to the light emitting diode row formed in series, and the light emitting diode row has a resistance value greater than that of the first resistance means. And a fourth light emitting diode array in which two resistance means are electrically connected in series, and each of the third light emitting diode array and the fourth light emitting diode array is provided outside the light emitting device array. The terminals are electrically connected in parallel, and the terminals are electrically connected to the constant current power supply unit.

  The first resistance means may be connected so as to electrically short-circuit the terminal and the third light emitting diode array substantially.

  According to said structure, the some light emitting diode row | line | column is electrically connected to the constant current power supply part in parallel via the respectively different resistance means. Since each resistance means generates a voltage drop proportional to the value of the flowing current, the magnitude of the voltage applied to each LED series electrically connected in series is changed to limit the value of the current flowing through the LED array. To do.

  In the light emitting diode, there is a relationship in which the light emission intensity increases in proportion to the magnitude of the forward current. In this light-emitting device array, a large amount of current supplied from the constant current power supply unit is distributed to the light-emitting diode array in which the resistance value of the resistance means electrically connected in series to the light-emitting diode array is small, and the resistance value of the resistance means is A small amount of current is distributed to a large light-emitting diode array. For this reason, the light emitting diode row having a small resistance value of the resistance means electrically connected in series to the light emitting diode row emits light more strongly.

  On the other hand, when a disconnection occurs in any of the light emitting diode rows, the constant current power supply unit supplies all the power to the light emitting diode rows that are not disconnected. The constant current power supply unit supplies power so as to maintain the same current as the current value supplied before any light emitting diode is disconnected. Therefore, the current value consumed by the light emitting device array is a constant value regardless of the disconnection of the light emitting diode.

  Therefore, in this light emitting device array, a constant light emission intensity can be maintained regardless of the disconnection of the light emitting diode.

  In order to solve the above problems, a light emitting device array of the present invention is a light emitting device array in which a plurality of light emitting diodes are driven by electric power supplied from a constant current power supply unit, and the light emitting diodes are electrically connected in series. A plurality of light emitting diode rows formed in a connected manner are formed, and the number of light emitting diodes forming the light emitting diode rows is set for each light emitting diode row, and each light emitting diode row is arranged in the light emitting device array. Is electrically connected in parallel to a terminal provided outside, and the terminal is electrically connected to the constant current power source.

  According to said structure, the number of the light emitting diodes which form a light emitting diode row | line for every several light emitting diode row | line | column provided in the light-emitting device array may differ. Also in this case, each light emitting diode row is electrically connected to the constant current power supply unit in parallel.

  In a light-emitting diode array composed of a large number of light-emitting diodes, the voltage applied to each light-emitting diode is smaller than that of a light-emitting diode array composed of a small number of light-emitting diodes. For this reason, a light-emitting diode array composed of a large number of light-emitting diodes flows less current than a light-emitting diode array composed of a small number of light-emitting diodes. For this reason, a light-emitting diode array composed of a small number of light-emitting diodes emits light more strongly.

  On the other hand, when a disconnection occurs in any of the light emitting diode rows, the constant current power supply unit supplies all the power to the light emitting diode rows that are not disconnected. The constant current power supply unit supplies power so as to maintain the same current value as that supplied before disconnection of any light emitting diode row. Therefore, the current value consumed by the light emitting device array is a constant value regardless of the disconnection of the light emitting diode array.

  The above disconnection is likely to occur when the light emitting diode consumes power, and thus easily occurs in the light emitting diode row through which a large amount of power flows. When a break occurs in a light-emitting diode array in which a large amount of power flows, that is, a light-emitting diode array composed of a small number of light-emitting diodes, the constant current power supply unit supplies all power to the light-emitting diode array that has not been disconnected. Supply. In other words, the current is redistributed to the light-emitting diode array composed of more light-emitting diodes.

  At this time, the current value supplied to the light-emitting device array is the same as that before the disconnection occurs, but the light-emitting diode array that did not cause the disconnection is more electrically in series than the light-emitting diode array that caused the disconnection. Since the number of light-emitting diodes connected to is large, the redistributed current is supplied to many light-emitting diodes connected in series. That is, the light emitting device array emits light more strongly than before the light emitting diode is disconnected.

  The first light emitting diode array and the second light emitting diode array may each be formed of one light emitting diode.

  According to the above configuration, since the light emitting diodes having different I (Vf) characteristics are electrically connected in parallel to the constant current power supply unit, the light emitting diode having a large I (Vf) is used for a light emitting diode having a small I (Vf). More current flows and emits light strongly.

  On the other hand, when the disconnection occurs in any of the light emitting diodes, the constant current power supply unit supplies all the power to the light emitting diodes that are not disconnected. The constant current power supply unit supplies power so as to maintain the same current as the current value supplied before any light emitting diode is disconnected. Therefore, the current value consumed by the light emitting device array is a constant value regardless of the disconnection of the light emitting diode.

  Therefore, in this light emitting device array, a constant light emission intensity can be maintained regardless of the disconnection of the light emitting diode.

  Further, the third light emitting diode array and the fourth light emitting diode array may each be formed of one light emitting diode.

  According to said structure, the some light emitting diode is electrically connected to the constant current power supply part in parallel via the respectively different resistance means. Since each resistance means causes a voltage drop proportional to the value of the flowing current, the magnitude of the voltage applied to the light emitting diodes electrically connected in series is changed to limit the value of the current flowing through the light emitting diode.

  In the light emitting diode, there is a relationship in which the light emission intensity increases in proportion to the magnitude of the forward current. In this light emitting device array, a large amount of current supplied from the constant current power source is distributed to the light emitting diodes having a small resistance value electrically connected to the light emitting diodes in series, and the resistance means has a large resistance value. Less current is distributed to the diode. Therefore, the light emitting diode having a small resistance value of the resistance means electrically connected in series to the light emitting diode emits light more strongly.

  On the other hand, when the disconnection occurs in any of the light emitting diodes, the constant current power supply unit supplies all the power to the light emitting diodes that are not disconnected. The constant current power supply unit supplies power so as to maintain the same current as the current value supplied before any light emitting diode is disconnected. Therefore, the current value consumed by the light emitting device array is a constant value regardless of the disconnection of the light emitting diode.

  Therefore, in this light emitting device array, a constant light emission intensity can be maintained regardless of the disconnection of the light emitting diode.

  In addition, each terminal included in the light emitting device array described above is electrically connected in series between the light emitting device arrays, and is also electrically connected in series to the constant current power supply unit. It may be.

  According to the above configuration, even if a disconnection occurs in any of the light emitting diodes included in each light emitting device array, the constant current power supply unit supplies all power via the light emitting diodes that do not cause the disconnection. Supply. The constant current power supply unit supplies power so as to maintain the same current as the current value supplied before any light emitting diode is disconnected. Therefore, the current value consumed in each of the light emitting devices is a constant value regardless of the disconnection of the light emitting diode.

  Therefore, in this light emitting device array, a constant light emission intensity can be maintained regardless of the disconnection of the light emitting diode.

  The light emitting diode may be configured by a bullet-shaped light emitting diode element.

  The light emitting diode may be configured by a light emitting diode element having a shape mounted on the surface of the substrate.

  In order to solve the above-described problems, the illumination device of the present invention is characterized by using the light-emitting device array described above as a light source.

  In order to solve the above-described problems, the illumination device of the present invention is characterized in that the light-emitting device array described above is used as a light source of a backlight.

  As described above, the light emitting device array of the present invention includes a plurality of light emitting diode rows formed by electrically connecting the same number of light emitting diodes in series, the first light emitting diode row and the first light emitting diode row. A second light emitting diode row having a larger I (Vf), and the first light emitting diode row and the second light emitting diode row are respectively connected to terminals provided outside the light emitting device array. The terminals are electrically connected in parallel, and the terminals are electrically connected to the constant current power supply unit.

  In addition, as described above, the light-emitting device array of the present invention includes a first resistor means electrically connected in series to a light-emitting diode array formed by connecting the same number of light-emitting diodes in series. Three light emitting diode rows, and a fourth light emitting diode row in which second resistor means having a resistance value larger than that of the first resistor means are electrically connected in series to the light emitting diode rows, and the third light emitting diode row is formed. Each of the light emitting diode row and the fourth light emitting diode row is electrically connected in parallel to a terminal provided outside the light emitting device, and the terminal is electrically connected to the constant current power supply unit. .

  In addition, as described above, the light-emitting device array of the present invention includes a plurality of light-emitting diode arrays formed by connecting light-emitting diodes electrically in series, and the light-emitting diode arrays forming the light-emitting diode arrays. The number is set for each light emitting diode row, and each light emitting diode row is electrically connected in parallel to a terminal provided outside the light emitting device, and the terminal is electrically connected to the constant current power supply unit. Connected to.

  In addition, as described above, the lighting device of the present invention uses the light-emitting device array described above as a light source.

  In the illumination device of the present invention, as described above, the light-emitting device array described above is used as the light source of the backlight.

  According to these configurations, when a plurality of light emitting diode arrays having different I (Vf) characteristics are electrically connected in parallel to the constant current power supply unit, the light emitting diode array having a small I (Vf) has I (Vf). More current flows than a large light emitting diode.

  In addition, when the plurality of light emitting diode arrays are electrically connected in parallel to the constant current power supply unit via different resistance means, each resistance means generates a voltage drop proportional to the value of the flowing current. Therefore, the magnitude of the voltage applied to the light emitting diode arrays electrically connected in series is changed to limit the value of the current flowing through the light emitting diode arrays.

  In the light emitting diode, there is a relationship in which the light emission intensity increases in proportion to the magnitude of the forward current. Therefore, in this light emitting device array, the light emitting diode array having a small I (Vf) is generated by the power supplied from the constant current power supply unit. It emits light more strongly than a light emitting diode array having a large (Vf).

  On the other hand, when a disconnection occurs in any of the light emitting diode rows, the constant current power supply unit supplies all the power to the light emitting diode rows that are not disconnected. The constant current power supply unit supplies power so as to maintain the same current as the current value supplied before any light emitting diode is disconnected. Therefore, the current value consumed by the light emitting device array is a constant value regardless of the disconnection of the light emitting diode.

  Therefore, in this light emitting device array, a constant light emission intensity can be maintained regardless of the disconnection of the light emitting diode.

  Further, the number of light emitting diodes forming the light emitting diode rows may be different for each of the plurality of light emitting diode rows provided in the light emitting device array. Also in this case, each light emitting diode row is electrically connected to the constant current power supply unit in parallel.

  In a light-emitting diode array composed of a large number of light-emitting diodes, the voltage applied to each light-emitting diode is smaller than that of a light-emitting diode array composed of a small number of light-emitting diodes. For this reason, a light-emitting diode array composed of a large number of light-emitting diodes flows less current than a light-emitting diode array composed of a small number of light-emitting diodes. For this reason, a light-emitting diode array composed of a small number of light-emitting diodes emits light more strongly.

  On the other hand, when a disconnection occurs in any of the light emitting diode rows, the constant current power supply unit supplies all the power to the light emitting diode rows that are not disconnected. The constant current power supply unit supplies power so as to maintain the same current value as that supplied before disconnection of any light emitting diode row. Therefore, the current value consumed by the light emitting device array is a constant value regardless of the disconnection of the light emitting diode array.

  The above disconnection is likely to occur when the light emitting diode consumes power, and thus easily occurs in the light emitting diode row through which a large amount of power flows. When a break occurs in a light-emitting diode array in which a large amount of power flows, that is, a light-emitting diode array composed of a small number of light-emitting diodes, the constant current power supply unit supplies all power to the light-emitting diode array that has not been disconnected. Supply. In other words, the current is redistributed to the light-emitting diode array composed of more light-emitting diodes.

  At this time, the current value supplied to the light-emitting device array is the same as that before the disconnection occurs, but the light-emitting diode array that did not cause the disconnection is more electrically in series than the light-emitting diode array that caused the disconnection. Since the number of light-emitting diodes connected to is large, the redistributed current is supplied to many light-emitting diodes connected in series. That is, the light emitting device array emits light more strongly than before the light emitting diode is disconnected.

  Therefore, there is an effect that it is possible to provide a light emitting device array and an illuminating device that do not cause nonuniformity in light emission intensity between the light emitting device arrays due to a failure occurring in a part of the light emitting device array.

  The present invention is not limited to the configurations described above, and various modifications are possible within the scope of the claims, and the invention can be obtained by appropriately combining the technical means disclosed above. Embodiments are also included in the technical scope of the present invention.

  As described above, according to the present invention, each light emitting device array includes a light emitting element that emits light strongly and a light emitting element that emits light weakly in a normal state. It is possible to emit light having the intensity emitted by the light emitting device array before the light emitting element is disconnected. Therefore, the present invention can be widely applied in fields where a light emitting device array that requires a certain light intensity, such as lighting or a backlight of a liquid crystal screen, needs to keep the light intensity stably.

It is a block diagram which shows one Embodiment of the light-emitting device array in this invention. It is a graph which shows one Embodiment of the light-emitting device array in this invention, and is a graph which shows the electrical characteristic of the forward voltage and forward current of LED of FIG. It is a block diagram which shows one Embodiment of the light-emitting device array in this invention, and is a block diagram which shows a mode that one light-emitting device of FIG. 1 was electrically connected. It is a block diagram which shows another one Embodiment of the light-emitting device array in this invention. It is a block diagram which shows another one Embodiment of the light-emitting device array in this invention. It is a block diagram which shows another one Embodiment of the light-emitting device in this invention. It is a block diagram which shows another one Embodiment of the light-emitting device in this invention. It is a block diagram which shows another one Embodiment of the light-emitting device array in this invention. It is a block diagram which shows another one Embodiment of the light-emitting device array in this invention. It is a block diagram which shows another one Embodiment of the light-emitting device array in this invention. It is a block diagram which shows the conventional light-emitting device array. It is a block diagram which shows the conventional light-emitting device array. It is a graph which shows the relationship between the forward current of common LED, and emitted light intensity. It is a graph which shows the electrical property of the forward voltage and forward current of LED with which the conventional light-emitting device array is provided. It is sectional drawing which shows the conventional light-emitting device. It is sectional drawing which shows the conventional light-emitting device. It is sectional drawing which shows the conventional light-emitting device. It is a block diagram which shows the conventional light-emitting device array.

Explanation of symbols

100, 200, 500, 600, 700 Light emitting device array 110, 210, 710 Constant current source (constant current power supply unit)
111, 211, 221, 721 Positive electrode (terminal)
112, 212, 222, 722 Negative electrode (terminal)
120,220 Light-emitting device 121,221,721 LED
(Light-emitting diodes that emit light mainly, light-emitting diodes)
122, 222, 722 LED
(Light-emitting diodes and light-emitting diodes that emit secondary light)
131 LED row
(Power supply line, LED array, first LED array)
132 LED row
(Power supply line, LED array, second LED array)
231 LED string
(Power supply line, LED array, third LED array)
232 LED string
(Power supply line, LED array, LED array 4)
731 732 LED row
(Power supply line, LED array)
213 Current limiting resistor
(Resistance, current limiting means, first resistance means)
214 Current limiting resistor
(Resistance, current limiting means, second resistance means)
300,400 light emitting device

Claims (12)

In a light emitting device array configured by connecting at least one light emitting device in series so as to span one constant current power supply unit, a plurality of power supply lines connected in parallel thereto, and a plurality of power supply lines,
Each light emitting device emits a secondary light having a light emission intensity smaller than that of a light emitting diode that emits light principally and a diode that emits light mainly due to a difference in forward current with respect to the same forward voltage during initial driving. A predetermined number of light emitting diodes are included, and have independent pairs of terminals corresponding to each light emitting diode,
Each light emitting diode is connected to a separate power supply line so as to have the same forward current-light emission characteristic in each current supply line.   2. The light emitting device array according to claim 1, wherein the current limiting means is connected only to a power supply line to which a light emitting diode that emits secondary light is connected.   A current limiting means is connected to each power supply line, and the current limit of the power supply line connected to the light emitting diode that emits secondary light is set to be larger than that of the light emitting diode that mainly emits light. The light-emitting device array according to claim 1. In a light-emitting device array configured by connecting at least one light-emitting device in series with one constant-current power supply unit and one power supply line and power supply line connected in parallel with each other,
Each light-emitting device includes a predetermined number of light-emitting diodes that mainly emit light and a number of light-emitting diodes that emit secondary light whose intensity is lower than the diode that mainly emits light due to the difference in the number of light-emitting diodes during initial driving. Each light-emitting diode is connected in parallel in the light-emitting device, and is collectively connected to a pair of terminals provided in the light-emitting device connected to the power supply line.   5. The light emitting device array according to claim 4, wherein the current limiting means is connected only to a diode that emits light in the light emitting device.   5. The light emitting device array according to claim 1, wherein the diode that mainly emits light has a larger forward current with respect to the same forward voltage than the diode that emits light secondarily.   The light emitting device array according to claim 2, 3 or 5, wherein the current limiting means is a resistor. One constant current power supply unit, a plurality of power supply lines connected in parallel thereto, and a light emitting diode array in which a plurality of light emitting diodes having the same forward current-light emission characteristic are connected in series for each power supply line In the light emitting device array provided with the light emitting device,
There are two types of light-emitting diode arrays: light-emitting diode arrays that mainly emit light and light-emitting diode arrays that emit light that is smaller than the light-emitting intensity. A light emitting device array, wherein a larger number of light emitting diodes are included than a light emitting diode array to be connected.   The light-emitting device array according to claim 1, wherein the light-emitting diode is formed of a bullet-shaped light-emitting diode element.   The light-emitting device array according to any one of claims 1 to 8, wherein the light-emitting diode is formed of a light-emitting diode element having a shape mounted on a substrate surface.   11. A lighting device using the light emitting device array according to claim 1 as a light source.   The light-emitting device array of any one of Claims 1-10 is used as a light source of a backlight, The illuminating device characterized by the above-mentioned.

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