HK1152759B - Light source unit, light source apparatus and projector - Google Patents

Description

Light source unit, light source device, and projector

Technical Field

The present invention relates to a light source unit including a plurality of light sources, a light source device including the light source unit, and a projector including the light source device.

Background

In these days, data projectors are widely used as image projection apparatuses that project images such as personal computer screens, video images, and images of image data stored in memory cards on to a screen. The projector condenses light emitted from a light source on a micro-mirror display device called a DMD (digital micro-mirror device) or a liquid crystal panel, and displays a color image on a screen.

In such a projector, a high-luminance discharge lamp has been mainly used as a light source. In recent years, development and proposal of a light emitting element using a Light Emitting Diode (LED), a Laser Diode (LD), or a semiconductor light emitting element such as an organic EL as a light source device have been increasing.

For example, japanese patent application laid-open No. 2004-220015 proposes a light source device in which light emitting elements are arranged in a matrix to increase the amount of light. However, in the invention of patent document 1, since the light emitting area increases and the value of Etendue (Etendue) increases, there is a problem that the light becomes unnecessary light in a large amount, and the utilization efficiency of the light emitted from the light emitting diode decreases. The etendue is a value representing the spatial range of effective light as the product of the area and the solid angle, and is also a value stored in the optical system.

Therefore, japanese patent application laid-open No. 2004-341105 proposes a light source device including a light emitting wheel and an ultraviolet light emitting diode in which a phosphor is laid in a circumferential direction. In the proposal of jp 2004-341105 a, the light source device is configured to irradiate ultraviolet light as excitation light from the inner surface side to a light emitting wheel (lighting wheel), and to use fluorescence emitted from the front surface side of the light emitting wheel as light source light.

In the invention of the above-mentioned japanese patent application laid-open No. 2004-341105, in order to increase the light intensity of fluorescence, it is necessary to increase the output of excitation light. As a method of increasing the output of the excitation light, there is a method of using a plurality of ultraviolet light emitting diodes, and in this case, since the bright spot (point ) of the excitation light source is increased, there is a problem that a large condenser lens is required to condense the light beams emitted from the plurality of bright spots on the phosphor.

Disclosure of Invention

The present invention has been made in view of the above-described problems of the prior art, and an object of the present invention is to provide a light source unit capable of reducing the cross-sectional area of light beams emitted from a plurality of bright points by reducing the interval between light beams emitted from the light sources by a mirror in a structure in which the plurality of light sources are arranged in a planar shape, a light source device including a light-emitting wheel using light emitted from the light source unit as excitation light and light of a predetermined wavelength range, and a small and thin projector including the light source device.

The light source unit, the light source device, and the projector according to the present invention are characterized by comprising a light source group in which a plurality of light sources are arranged in a planar shape so as to form rows and columns, and a first mirror group which is disposed on an optical axis of the light source group and reflects light beams emitted from the light source group into light beams narrowed in a column direction by narrowing a row interval of the light beams emitted from the light source group.

The present invention will be fully understood from the following detailed description and the accompanying drawings, which are given by way of illustration only and are not intended to limit the present invention.

Drawings

Fig. 1 is a perspective view schematically showing an appearance of a light source unit according to an embodiment of the present invention.

Fig. 2 is a perspective view schematically showing an external appearance of a light source unit according to an embodiment of the present invention.

Fig. 3 is a perspective view schematically showing an external appearance of a light source unit according to another embodiment of the present invention.

Fig. 4 is a perspective view schematically showing an external appearance of a light source unit according to another embodiment of the present invention.

Fig. 5 is a schematic diagram illustrating a reduction in the cross-sectional area of a light beam of a light source unit according to an embodiment of the present invention.

Fig. 6 is a perspective view showing an external appearance of an embodiment of a projector according to an embodiment of the present invention.

Fig. 7 is a functional circuit block diagram of a projector relating to an embodiment of the present invention.

Fig. 8 is a schematic plan view showing an internal structure of a projector according to an embodiment of the present invention.

Fig. 9 is a schematic plan view of a light source device provided in a projector according to an embodiment of the present invention.

Detailed Description

Preferred embodiments for carrying out the present invention will be described below with reference to the accompanying drawings. However, in the following embodiments, various technical preferable limitations for carrying out the present invention are added, but the scope of the present invention is not limited to the following embodiments and the accompanying examples.

The projector 10 of the present invention includes a light source device 63, a light guide device 75, a light source side optical system 62, a display element 51, a projection side optical system 90, and a projector control unit.

The light source device 63 includes a light source unit 200, a light-emitting wheel 71 disposed on the optical axis of the light beam emitted from the light source unit 200, a wheel motor 73 that rotationally drives the light-emitting wheel 71, and a red light source 72 that is a monochromatic light-emitting element. The light source device 63 has a condensing optical system that causes the optical axis of the light beam emitted from the light-emitting wheel 71 to coincide with the optical axis of the light beam emitted from the red light source 72, and condenses the light beam on the incident surface of the light guide device 75.

The light-emitting wheel 71 has at least a diffusion transmission region and a fluorescence reflection region, which are arranged in parallel in the circumferential direction. The diffuse transmission region is a region in which light emitted from the light source unit 200 using light of blue laser light as a light source is diffusely transmitted. The fluorescent light reflecting region is a region having a fluorescent material that emits light in the green wavelength band.

The light source unit 200 is composed of a light source group 210 and a first reflector group 220, the light source group 210 is arranged in a plane shape with a plurality of light sources 201 formed in rows and columns, the first reflector group 220 reflects light beams emitted from the light source group 210 into light beams with a reduced cross-sectional area in a column direction. The first reflector set 220 is disposed on the optical axis of the light source set 210. The first mirror group 220 reflects the light beams emitted from the light source group 210 into light beams having a reduced cross-sectional area in the column direction by reducing the row interval of the light beams emitted from the light sources 201 constituting each row of the light source group 210.

The light source 201 is formed by combining the light emitting element 205 and a collimator lens 207 that converts outgoing light from the light emitting element 205 into parallel light. The light source group 210 is arranged in 6 rows and 4 columns such that 24 light sources 201 form a rectangle.

The first mirror group 220 is configured by disposing different rectangular mirrors 225 (short ) in a stepwise manner on the optical axes of the light beams emitted from the respective rows of the light source group 210. The mirrors 225 are arranged so as to eliminate the mutual intervals of the reflected light from the mirrors 225.

Embodiments of the present invention are described in detail below with reference to the accompanying drawings. Fig. 1 and 2 are schematic views showing a three-dimensional appearance of a light source unit 200 according to the present invention. As shown in fig. 1 and 2, the light source unit 200 of the present invention includes: a light source group 210 in which a plurality of light sources 201 are arranged in rows and columns in a planar manner, a first mirror group 220 based on a plurality of mirrors 225 arranged on the optical axis of each light source 201 of the light source group 210, and a second mirror group 230 based on a plurality of mirrors 235 arranged on the optical axis of the light beam reflected by the first mirror group 220.

The light source unit 200 first converts the light beams emitted from the light source group 210 into light beams having a reduced cross-sectional area in the column direction by the first mirror group 220. Then, the light source unit 200 converts the light beams emitted from the light source group 210 into light beams having a cross-sectional area reduced in a row direction, which is a direction perpendicular to the first mirror group 220, by the second mirror group 230. Such a light source unit 200 can reduce the cross-sectional area of light beams and increase the density of light beams without changing the diffusion angle of the light beams emitted from the light source group 210. In addition, the column direction is the up-down direction in the front view of fig. 1, and the row direction is the direction orthogonal to the column direction in the plane in which the light source groups 210 are arranged.

The light source 201 is formed by combining a light emitting element 205 which is a point light source such as a blue laser light emitter and a collimator lens 207 which converts a light flux emitted from the light emitting element 205 into parallel light having increased directivity.

The light source group 210 is configured such that 24 light sources 201 are arranged in 6 rows and 6 columns so as to form an octagon with parallel opposing sides. That is, the light source group 210 is configured such that the light sources 201 formed in the first row 2, the second row 4, the third row 6, the fourth row 6, the fifth row 4, and the sixth row 2 are arranged at regular intervals, and similarly, in the column direction, the light sources 201 formed in the 2, 4, 6, 4, and 2 are arranged sequentially at regular intervals, and are formed in an octagonal shape with 2 sides parallel to each other. The predetermined interval is provided between the light sources 201 in this manner in order to secure a space for arranging the substrates for the light sources 201, a space for holding members for holding the light sources 201, and a space for wiring. The light sources 201 are spaced apart from each other by a predetermined distance to provide a measure against heat of the light sources 201.

The first reflector group 220 is composed of 6 rectangular reflectors 225, i.e., reflectors 225 having the same number of rows as the light sources 201 of the light source group 210. The 6-piece mirror 225 reduces the line interval of the light beams emitted from the light sources 201 positioned in each line of the light source group 210, and reflects the light beams with a reduced cross-sectional area in the column direction. The 6-piece mirrors 225 each include: 2 pieces of 2 light source mirrors 225 corresponding to the row in which 2 light sources 201 are arranged, 2 pieces of 4 light source mirrors 225 having a width wider than that of the 2 light source mirrors 225, and 2 pieces of 6 light source mirrors 225 having a width wider than that of the 4 light source mirrors 225.

The first mirror group 220 is configured such that the different rectangular mirrors 225 are arranged at an angle of 45 degrees with respect to the optical axis in a step-like manner on the optical axis of the light beams emitted from the respective rows of the light source group 210. The mirrors 225 are arranged so as to eliminate the mutual intervals between the reflected lights from the mirrors 225, that is, so as to shorten the mutual intervals between the mirrors 225 in the optical axis direction of the light emitted from the light source group 210.

That is, on the optical axis of the row in which 2 light sources 201 are arranged, 2 light source mirrors 225 are arranged at an angle of 45 degrees with respect to the optical axis, on the optical axis of the row in which 4 light sources 201 are arranged, 4 light source mirrors 225 are arranged at an angle of 45 degrees with respect to the optical axis, and on the optical axis of the row in which 6 light sources 201 are arranged, 6 light source mirrors 225 are arranged at an angle of 45 degrees with respect to the optical axis.

In the first mirror group 220, the mirrors 225 are arranged in a stepwise manner in order to prevent the light beam reflected by each mirror 225 from interfering with the other mirrors 225. The mirrors 225 are arranged so as to eliminate the mutual intervals of the reflected light from the mirrors 225, and are reflected as a light flux whose cross-sectional area is reduced in the column direction by excluding the space between the rows of the light source group 210.

The second mirror group 230 is composed of 6 rectangular mirrors 235, that is, mirrors 235 having the same number of rows of light sources 201 as that of the light source group 210. The 6 reflecting mirrors 235 are configured such that the different rectangular reflecting mirrors 235 are arranged in a step-like manner on the optical axis of the light flux emitted from each row of the light source group 210 and reflected by the first reflecting mirror group 220. Further, the 6 mirrors 235, like the first mirror group 220, respectively include: 2 light source mirrors 235 corresponding to the row in which 2 light sources 201 are arranged, 2 light source mirrors 235 each having a width larger than that of the 2 light source mirrors 235, 4 light source mirrors 235 each having a width larger than that of the 2 light source mirrors 235, and 6 light source mirrors 235 each having a width larger than that of the 4 light source mirrors 235.

Each mirror 235 is disposed at an angle of 45 degrees with respect to the optical axis of the light flux emitted from each row of the light source group 210 and reflected by the first mirror group 220. That is, the second mirror group 230 converts the optical axis of the light beam reflected by the first mirror group 220 into a direction perpendicular to the optical axis and the optical axis of the light source group 210. The mirrors 235 are arranged so as to eliminate the mutual intervals of the reflected lights from the mirrors 235, that is, so as to shorten the mutual intervals of the mirrors 235 in the optical axis direction of the reflected lights reflected by the first mirror group 220.

The second reflecting mirror group 230 reduces the length of the light beam emitted from the light source group 210 in the row direction, thereby reducing the cross-sectional area of the light beam in the row direction and increasing the density of the light beam. That is, according to the second mirror group 230, the length in the direction orthogonal to the direction narrowed by the first mirror group 220 can be narrowed in the cross section of the light beam emitted from the light source group 210. Thus, the light source unit 200 of the present embodiment can emit a light beam with a small cross-sectional area and high brightness.

Further, although the plurality of mirrors 225 and 235 have different lengths corresponding to the number of light sources 201 arranged in the corresponding row or the corresponding column, all the mirrors 225 and 235 may have the same size and may be freely changed in accordance with the configuration space and the configuration place of the light source unit 200 of the electronic device in which the light source unit 200 is used.

Next, another embodiment of the light source unit 200 configured to reduce the cross-sectional area of the light flux emitted from the light source group 210 will be described. Fig. 3 is a perspective view schematically showing an external appearance of a light source unit 200 according to another embodiment. In the light source unit 200, the light emitted from the light source group 210 is reduced in 2 directions, but as shown in fig. 3, the first mirror group 220 may be disposed on the optical axis of the light source group 210, and the cross-sectional area of the light flux may be reduced in only one direction.

The light source unit 200 configured as above includes a light source group 210 and a first mirror group 220, and the first mirror group 220 is disposed on an optical axis of a light beam emitted from the light source group 210 and performs 90-degree conversion on the optical axis. The light source group 210 is configured such that a plurality of light source bodies, each of which is formed by linearly arranging a plurality of light sources 201 adjacent to each other, are arranged in a planar shape with a space therebetween so as to form a heat radiation space between the light source bodies. The 24 light sources 201 each including the light emitting element 25 and the collimator lens 207 are arranged in 6 rows and 4 columns at equal intervals so as to form a rectangle.

The first mirror group 220 is composed of 6 rectangular mirrors 225. The first mirror group 220 is configured such that the different rectangular mirrors 225 are arranged in a step-like manner on the optical axis of the light beams emitted from the respective rows of the light source group 210 at an angle of 45 degrees with respect to the optical axis. The 6-piece mirror 225 reduces the line interval of the light flux emitted from the light source 201 positioned in each line of the light source group 210, thereby reflecting the light flux into a light flux having a reduced cross-sectional area in the column direction. The mirrors 225 are arranged so that the mutual intervals between the reflected lights from the mirrors 225 are eliminated, that is, so that the mutual intervals between the mirrors 225 are shortened in the optical axis direction of the light emitted from the light source group 210.

In an apparatus in which a plurality of light sources are arranged in parallel, when the plurality of light sources require a heat radiation space from each other, the light sources are arranged with a predetermined interval therebetween. However, in this type of device, since the light sources are arranged with a predetermined interval therebetween, the cross-sectional area of the light beam emitted from the plurality of light sources is enlarged. The light source unit 200 of the present embodiment is of a structure: even if a plurality of light sources are arranged at predetermined intervals, the first mirror group 220 can reduce the cross-sectional area of the light beams emitted from the light source groups and emit light beams with increased density.

Further, the light source unit 200 according to another embodiment will be described. Fig. 4 is a schematic diagram showing a three-dimensional appearance of the light source unit 200 of the present embodiment. In the light source unit 200 of the present embodiment, as shown in fig. 3, in the light source unit 200 configured to arrange the first mirror group 220 on the optical axis of the light source group 210 and reduce the cross-sectional area of the light flux only in one direction, as shown in fig. 4, the first mirror group 220 is configured such that the light emitted from one light source 201 is reflected by one mirror 225.

That is, in the light source unit 200 of the present embodiment, the first mirror group 220 includes the same number of mirrors 225 as the number of light sources 201 of the light source group 210, the mirrors 225 are arranged at the same inclination on the optical axis of the light sources 201 of the light source group 210, and the mirrors 225 are arranged so as to eliminate the mutual interval of the reflected light from the mirrors 225, that is, so as to shorten the mutual interval of the mirrors 225 in the optical axis direction of the light source group 210.

In the light source unit 200 of the present embodiment, the mirrors 225 are arranged at the same inclination, but the mirrors 225 may be arranged at different inclinations so that the light emitted from the light sources 201 is converged to a predetermined point.

Next, in each of the above embodiments, the principle of reducing the cross-sectional area of the light beam emitted from the light source group 210 by the mirror group 220, 230 will be described, taking the first mirror group 220 as an example. Fig. 5 is a reference diagram for explaining the principle of reducing the cross-sectional area of the light beams by the first mirror group 220 of the present embodiment. The light beams emitted from the collimator lens 207 of the light source 201 are parallel light beams.

When the diameter of the collimator lens 207 of the light source 201 is a and the row interval between the light sources is b, as shown in fig. 5, the total length of the light source group 210 in the column direction is 6a +5b because of 6 columns, and since all the light beams emitted from the collimator lens 207 of the light source 201 are parallel light, the total length of the light beams emitted from the light source group 210 in the column direction of the cross-sectional area is also 6a +5 b.

When the light flux emitted from the light source group 210 is reflected at right angles to the column direction by one mirror 220e, the total length in the column direction of the cross section of the light flux reflected by the mirror 220e becomes 6a +5 b. However, in the present embodiment, the different rectangular mirrors 225 are arranged in each row, and the mirrors 225 are arranged so that the distance between the mirrors 225 is shortened in the optical axis direction of the light source group 210. Thus, the light flux reflected by each mirror 225 becomes a light flux in a state where the interval b between the light sources 201 of the light source group 210 is deleted, and the entire length of the light flux in the column direction becomes 6 a.

According to the light source unit 200 configured as described above, since the first mirror group 220 is provided to reduce the line interval of the light beams emitted from the light sources 201 in each line constituting the light source group 210 and reflect the light beams with a reduced cross-sectional area in the column direction, the light beams emitted from the light source group 210 can be made to have a reduced cross-sectional area in a predetermined direction, and the etendue of the light source unit 200 can be reduced.

Further, by configuring the first mirror group 220 by disposing the plurality of mirrors 225 in a stepwise manner on the optical axis of the light beams emitted from the respective rows of the light source group 210, and by disposing the light source units 200 of the respective mirrors 225 so as to eliminate the mutual intervals of the reflected light from the respective mirrors 225, it is possible to prevent the light beams reflected by the respective mirrors 225 from interfering with the other mirrors 225 and to reflect the light beams as the light beams with the intervals between the light sources 201 in the row direction of the light source group 210 eliminated.

Further, the first mirror group 220 is constituted by the rectangular mirrors 225 having the same number of rows as the light sources 201 of the light source group 210, and the light source unit 200 constituted by disposing the respective mirrors 225 at the same inclination so as to be parallel to the row direction of the light source group 210 can emit the light flux having the cross-sectional area reduced in a predetermined one direction while maintaining the diffusion angle emitted from the collimator lens 207, and can reduce the etendue of the light source unit 200.

In addition, the first mirror group 220 is configured by the same number of mirrors 225 as the number of light sources 201 of the light source group 210, and according to the light source unit 200 configured by disposing the respective mirrors on the optical axis of the respective light sources 201 of the light source group 210 with a predetermined inclination with respect to the optical axis, since the mirrors 225 corresponding to the respective light sources 201 are present, even when the arrangement of the light sources 201 of the light source group 210 is irregular or the like, the cross-sectional area of the light flux can be easily reduced.

Further, according to the light source unit 200 including the second mirror group 230 on the optical axis of the light beam reflected by the first mirror group 220, the light beam emitted from the light source group 210 can be reduced in cross-sectional area in the direction orthogonal to the direction of reflection by the first mirror group 220, and therefore, the cross-sectional area of the light beam can be reduced in two directions orthogonal to the plane.

Further, the second mirror group 230 is similar to the first mirror group 220 in that, in the light source unit 200 in which the plurality of rectangular mirrors 235 are arranged so as to eliminate the intervals between the reflected lights from the mirrors 235, the light beams reflected by the mirrors 235 can be reflected as the light beams with the intervals between the light sources 201 in the column direction of the light source group 210 eliminated while preventing the interference with the other mirrors 235, as in the first mirror group 220.

In addition, according to the light source unit 200 of the present embodiment, the first mirror group 220 and the second mirror group 230 can reduce the cross-sectional area of the light beam emitted from the light source group 210 in two orthogonal directions, and can increase the density of the light beam. Further, by using the light source unit 200, a small lens having a small diameter or the like can be used as an optical system, and a small and thin electronic device capable of emitting high-luminance light can be provided.

The first mirror group 220 and the second mirror group 230 are not limited to being arranged at an angle of 45 degrees with respect to the optical axis of the light source 201, and the distance and angle with respect to the light source 201 may be adjusted to reduce the interval between the lights in a row or a column.

Further, since the light source 201 is configured by combining the light emitting element 205 and the collimator lens 207, the light emitted from the light emitting element 205 is converted into parallel light by the collimator lens 207, and therefore, the utilization efficiency of the light emitted from the light source 201 can be improved.

In addition, since the light source group 210 is configured such that 24 light sources 201 are arranged in 6 rows and 6 columns so that two opposing sides thereof are formed into an octagonal shape in parallel, the cross-sectional shape of the light flux emitted from the light source group 210 is formed into a shape close to a circle, and thus the density of the light emitted from the light source unit 200 can be made uniform.

Further, according to the light source unit 200 of the present embodiment, even in the case where the light source groups 210 are arranged in 6 rows and 4 columns in such a manner that the 24 light sources 201 form a rectangle, for example, it is possible to easily change the sectional shape of the light beam, for example, to a light beam having a sectional shape conforming to the shape of the display element with a ratio of 4: 3, or a light beam having a square sectional shape.

Next, a projector 10 will be described as an example of an electronic device using such a light source unit 200. Fig. 6 is an external perspective view of the projector 10. In the present embodiment, the left and right represent the left and right direction with respect to the projection direction, and the front and back represent the front and back direction with respect to the traveling direction of the light beam. As shown in fig. 6, the projector 10 has a substantially rectangular parallelepiped shape, and a lens cover 19 for covering a projection opening is provided on a side of a front panel 12 which is a side plate in front of a main body case, and the front panel 12 has a plurality of exhaust holes 17. Although not shown, the projector 10 includes an Ir receiving unit that receives a control signal from a remote controller.

Further, a key indicator portion 37 is provided on the top panel 11 as the main body case. The key indicator unit 37 is provided with a power switch key, a power indicator for notifying on or off of power, a projection switch key for switching on and off of projection, and a key and/or an indicator such as an overheat indicator for notifying when the light source device, the display element, the control circuit, or the like is overheated.

On the back surface of the main body case, various terminals 20 such as a USB terminal, an input/output connector section including a D-SUB terminal for inputting image signals, an S terminal, an RCA terminal, and the like, and a power adapter plug are provided on the back panel. Further, a plurality of intake holes 18 are formed in the vicinity of the lower portion of the right side plate 14, which is a side plate of the main body casing, not shown, and the left side plate 15, which is a side plate shown in fig. 6.

Next, a projector control unit of the projector 10 will be described with reference to a block diagram of fig. 7. The projector control unit is configured by a control unit 38, an input/output interface 22, an image conversion unit 23, a display encoder 24, a display drive unit 26, and the like. The image signals of various specifications input from the input/output connector section 21 are converted by the image conversion section 23 via the input/output interface 22 and the System Bus (SB) so as to be unified into image signals of a predetermined format suitable for display, and then output to the display encoder 24.

The display encoder 24 expands and stores the input image signal in the video RAM25, generates a video signal from the stored content of the video RAM25, and outputs the video signal to the display driver 26.

The display driving unit 26 drives the display element 51, which is a spatial light modulator (SOM), at an appropriate frame rate in accordance with the image signal output from the display encoder 24, and irradiates the display element 51 with a light beam emitted from the light source device 63 via the light source side optical system, thereby forming a light image by the reflected light of the display element 51 and projecting the display image on a screen, not shown, via a projection system lens group, which is a projection side optical system. In addition, the movable lens group 97 of the projection side optical system is driven for zoom adjustment and focus adjustment by the lens motor 45.

Further, the image compression/expansion unit 31 performs recording processing of: the luminance signal and the color difference signal of the image signal are data-compressed by ADCT and huffman coding, and are sequentially written into the memory card 32 which is a removable recording medium. In the playback mode, the image compander 31 performs the following processing: the image data recorded in the memory card 32 is read out, each image data constituting a series of moving pictures is expanded in units of 1 frame, and the image data is output to the display encoder 24 via the image conversion unit 23, so that the moving pictures and the like can be displayed based on the image data stored in the memory card 32.

The control unit 38 controls operations of the circuits in the projector 10, and includes a CPU, a ROM in which operation programs such as various settings are fixedly stored, a RAM used as a work memory (work memory), and the like.

An operation signal of a key indicator unit 37 including a main key and an indicator provided on the top panel 11 of the main body case is directly sent to the control unit 38, a key operation signal from the remote controller is received by the Ir receiving unit 35, and an encoded signal demodulated by the Ir processing unit 36 is output to the control unit 38.

The audio processing unit 47 is connected to the control unit 38 via a System Bus (SB). The audio processing unit 47 includes a sound source circuit such as a PCM sound source, and simulates audio data and drives a speaker 48 to perform sound amplification and reproduction in the projection mode and the reproduction mode.

The control unit 38 controls the light source control circuit 41, and the light source control circuit 41 controls the light source device 63 so that light of a predetermined wavelength band requested at the time of image generation is emitted from the light source device 63. Specifically, when light in the red wavelength band is requested, the light emitting elements 205 of the light source unit 200, which will be described later, are stopped from being turned on, and the light emitting elements of the red light source 72 are turned on. When light of the green wavelength band is requested, the light emitting element 205 of the light source unit 200 is turned on, and the wheel motor 73 is controlled to perform control such that the green fluorescence region is positioned on the optical axis of the light emitting element 205 of the light source unit 200. Further, when light of the blue wavelength band is requested, the light emitting element 205 of the light source unit 200 is lighted, and the wheel motor 73 is controlled to perform control to locate the diffusion transmission region on the optical axis of the light emitting element 205 of the light source unit 200.

The control unit 38 causes the cooling fan drive control circuit 43 to perform temperature detection by a plurality of temperature sensors provided in the light source device 63 and the like, and controls the rotation speed of the cooling fan based on the result of the temperature detection. Further, the control unit 38 performs control such that: the cooling fan drive control circuit 43 is configured to continue the rotation of the cooling fan even after the power supply of the projector main body is turned OFF (OFF) by a timer or the like, or to turn OFF the power supply of the projector main body based on the result of the temperature detection by the temperature sensor, or the like.

Next, the internal structure of the projector 10 will be described. Fig. 8 is a schematic plan view showing an internal structure of the projector 10. As shown in fig. 8, in the projector 10, a power control circuit board 102 on which a power circuit module 101 and the like are mounted is disposed near the right side panel 14, a Sirocco fan-type blower 110 is disposed substantially at the center, a control circuit board 103 is disposed near the blower 110, a light source device 63 is disposed near the front panel 12, and an optical system unit 70 is disposed near the left side panel 15.

In the projector 10, the partition wall 120 hermetically partitions the interior of the housing into an intake-side space chamber 121 on the rear panel 13 side and an exhaust-side space chamber 122 on the front panel 12 side, and the blower 110 is disposed such that the intake port 111 is located in the intake-side space chamber 121 and the exhaust port 113 is located at the boundary between the exhaust-side space chamber 122 and the intake-side space chamber 121.

The optical system unit 70 is substantially shaped like "コ" and includes 3 modules, i.e., an illumination-side module 78 located in the vicinity of the light source device 63, an image generation module 79 located on the rear panel 13 side, and a projection-side module 80 located between the illumination-side module 78 and the left side panel 15.

The illumination side block 78 includes a part of the light source side optical system 62, and the light source side optical system 62 guides light emitted from the light source device 63 to the display element 51 included in the image generation block 79. The light source side optical system 62 included in the illumination side block 78 includes a light guide device 75 for making the light flux emitted from the light source device 63 a light flux having a uniform intensity distribution, a condenser lens for condensing the light transmitted through the light guide device 75, and the like.

The image generation block 79 includes, as the light source side optical system 62: an optical axis changing mirror 74 for changing the optical axis direction of the light beam emitted from the light guide device 75; a plurality of condensing lenses for condensing the light reflected by the optical axis changing mirror 74 on the display element 51; and an irradiation mirror 84 for irradiating the display element 51 with the light beams transmitted through the condenser lenses at a predetermined angle. The image generation module 79 includes a DMD which is the display element 51, and a display element cooling device 53 for cooling the display element 51 is disposed on the rear panel 13 side of the display element 51, thereby preventing the display element 51 from becoming hot.

The projection side module 80 has a lens group of a projection side optical system 90 that emits light reflected by the display element 51 and forms an image to a screen. As the projection side optical system 90, a variable focus lens having a zoom function is used, which includes a fixed lens group 93 built in a fixed barrel and a movable lens barrel group 97 built in a movable barrel, and the projection side optical system 90 can perform zoom adjustment and focus adjustment by moving the movable lens group 97 by a lens motor.

Next, the light source device 63 of the projector 10 of the present embodiment is explained. Fig. 9 is a plan view of the light source device 63. As shown in fig. 9, the light source device 63 includes: a light source unit 200 disposed such that the central axis of the light guide device 75 is orthogonal to the optical axis; a light-emitting wheel 71 disposed on the optical axis of the light source unit 200 such that the optical axis of the light source unit 200 is parallel to the rotation axis; a wheel motor 73 that rotationally drives the light-emitting wheel 71; a red light source 72 as a monochromatic light emitting element, which is arranged in such a manner that the optical axis of the light source unit 200 is orthogonal to the optical axis; the condensing optical system is configured to cause the optical axis of the light beam emitted from the light-emitting wheel 71 and the optical axis of the light beam emitted from the red light source 72 to coincide with each other, and to condense the light beam on a predetermined surface.

As described above, the light source unit 200 includes the light source group 210 having the plurality of light sources 201, and the first mirror group 220 arranged in front of the light source group 210, which changes the optical axis by 90 degrees and reduces the cross-sectional area of the light beam, and the light source unit 200 emits the blue laser beam. The light source 201 is formed by combining a blue laser light emitter as the light emitting element 205 and a collimator lens 207 arranged in front of the light emitting element 205.

The light-emitting wheel 71 is formed by arranging at least a diffusion transmission region for diffusing light emitted from the light source unit 200 and a fluorescence reflection region having a fluorescent material for emitting light of a predetermined wavelength band in a circumferential direction. Specifically, a green phosphor layer including a green phosphor is laid on the fluorescence reflection region, and the surface of the light-emitting wheel 71 in the region where the green phosphor layer is laid is used as a reflection surface. The light-emitting wheel 71 emits the light of the green wavelength band fluorescent light to the light source unit 200 side by irradiating the green phosphor layer with the light emitted from the light source unit 200, and emits the light of the blue wavelength band diffused from the inner surface side by irradiating the diffusion transmission layer with the light emitted from the light source unit 200.

The red light source 72 is a light emitting element that emits red light, such as a red light emitting diode, and is disposed between the light source unit 200 and the light emitting wheel 71 so that the light emitted from the light source unit 200 is orthogonal to the optical axis.

The condensing optical system includes a lens group 151, a convex lens group 153, a condensing lens group 155, and a light guide incident lens group 154. The lens group 151 includes: a first mirror 151a disposed at a position orthogonal to the optical axis of the light emitting unit 200 and the optical axis of the red light source 72; a second mirror 151b disposed on the inner surface side of the light emitting wheel 71 at a position where an extension line of the central axis of the light guide device 75 intersects with an extension line of the optical axis of the light source unit 200; a third mirror 151c disposed on the optical axis of the red light source 72; and a fourth mirror 151d disposed at a position where the optical axis of the light in the red wavelength band reflected by the third mirror 151c intersects with an extension line of the central axis of the light guide device 75.

The first mirror 151a functions as a dichroic mirror, transmits light of a blue wavelength band and light of a red wavelength band, and reflects light of a green wavelength band. The second mirror 151b serves as a reflecting mirror, and aligns the optical axis of the light guide device 75 with the optical axis of the light of the blue wavelength band diffused and transmitted through the light emitting wheel 71. The third mirror 151c serves as a reflecting mirror for reflecting the light in the red wavelength band and the light in the green wavelength band toward the fourth mirror 151 d. The fourth mirror 151d serves as a dichroic mirror, and transmits light in the blue wavelength band and reflects light in the red wavelength band and light in the green wavelength band.

The convex lens group 153 as a condensing optical system includes: a first convex lens 153a disposed between the light source unit 200 and the first mirror 151 a; a second convex lens 153b disposed between the second mirror 151b and the fourth mirror 151 d; a third convex lens 153c disposed between the first mirror 151a and the third mirror 151 c; and a fourth convex lens 153d disposed between the third mirror 151c and the fourth mirror 151 d.

The condenser lens group 155, which is a condensing optical system, is disposed in the vicinity of the red light source 72 and in the vicinity of both the inner and outer surfaces of the light-emitting wheel 71, and condenses light emitted from the red light source 72 and the light-emitting wheel 71. The light guide device incident lens 154 as a condensing optical system is disposed in the vicinity of the light guide device 75, and condenses the light in the red wavelength band, the light in the green wavelength band, and the light in the blue wavelength band from the light source device 63 on the incident surface of the light guide device 75.

In the light source device 63, the blue laser beam emitted from the light source unit 200 is condensed by the first convex lens 153a, then passes through the first mirror 151a, and is irradiated to the fluorescence reflection region and the diffusion transmission region of the light emitting wheel 71 through the condensing lens group 155. The light beam emitted from the light source unit 200 and irradiated to the fluorescent reflection region excites the phosphor as excitation light, and the phosphor emits light of a green wavelength band. The light beam emitted from the light source unit 200 and irradiated to the diffusion and transmission region of the light-emitting wheel 71 is diffused, and the light beam is converted from coherent light to incoherent light, and light in the blue wavelength band, which is incoherent light, is emitted from the inner surface side of the light-emitting wheel 71.

The light in the red wavelength band emitted from the red light source 72 is condensed by the condenser lens group 155, and is transmitted through the first mirror 151 a. The light of the green wavelength band emitted from the light-emitting wheel 71 in the direction of the light source unit 200 is condensed by the condenser lens group 155 and is irradiated to the first mirror 151 a. The light in the red wavelength band transmitted through the first mirror 151a and the light in the green wavelength band reflected by the first mirror 151a are condensed by the third convex lens 153c and the fourth convex lens 153d, are reflected by the third mirror 151c and the fourth mirror 151d, are condensed on the incident surface of the light guide device 75 by the light guide device incident lens 154, and are incident on the light guide device 75. The light of the blue wavelength band diffused and transmitted through the light emitting wheel 71 is condensed by the condenser lens group 155, is irradiated to the second mirror 151b, is reflected by the second mirror 151b, is condensed by the second convex lens 153b, is transmitted through the fourth mirror 151d, is condensed by the light guide incident lens 154 at the incident surface of the light guide 75, and is incident into the light guide 75.

The light source device 63 can emit light in a red wavelength band, light in a green wavelength band, and light in a blue wavelength band, which are three primary colors of light. Therefore, the projector 10 of the present embodiment can emit light in a desired wavelength band for generating an image by controlling the light emitting element 205, the red light source 72, and the light emitting wheel 71 of the light source unit 200 by the light source control circuit 41, and can realize color projection of an image by reflecting the light in the predetermined wavelength band as a component of the image on the projection side optical system 90 by the display element 51.

According to the light source device 63 of the present embodiment, as described above, the light source unit 200 that irradiates the light emitting wheel 71 with the light as the excitation light and the light in the blue wavelength band can emit the light flux with high luminance, small cross-sectional area, and high density, and therefore, the light source device 63 in the projector 10 that can project an image with high luminance and high brightness can be used.

Further, according to the light source device 63 of the present embodiment, the light in the green wavelength band is emitted from the fluorescence reflection region of the light-emitting wheel 71, the light in the blue wavelength band is emitted from the diffusion transmission region of the light-emitting wheel 71, and the light in the red wavelength band is emitted from the independent red light source 72 by using the blue laser emitter as the light-emitting element 205 of the light source unit 200, and with this configuration, the luminance and brightness of the light flux of the light in each wavelength band can be made largely uniform, so that it is possible to prevent the difference in brightness or the like from occurring in the projected image when the projector 10 projects an image.

Further, according to the projector 10 including the light source device 63, it is possible to project a projection image having high luminance and brightness and uniform luminance and brightness of light in all wavelength bands.

According to the present invention, in a configuration in which a plurality of light sources are arranged in a plane, the interval between light emitted from the light sources is reduced by a reflector, and thereby, it is possible to provide: a light source unit capable of reducing a cross-sectional area of a light beam emitted from a plurality of bright points; a light source device including a light emitting wheel that uses light emitted from the light source unit as excitation light and light of a predetermined wavelength range; and a small and thin projector provided with the light source device.

The present invention is not limited to the above-described embodiments, and various modifications may be made in the implementation stage without departing from the scope of the main idea thereof. Further, the functions performed in the above embodiments may be implemented by combining the functions as appropriate as possible. The embodiments described above include various stages, and various inventions can be summarized based on appropriate combinations of a plurality of disclosed structural elements. For example, even if some of the constituent elements shown in the embodiments are deleted, if an effect can be obtained, a structure in which the constituent elements are deleted can be summarized as an invention.

Claims (10)

1. A light source unit is characterized by comprising:

a light source group in which a plurality of light sources are arranged in a planar shape so as to form rows and columns; and

a first mirror group disposed on an optical axis of the light source group, for reflecting the light beams emitted from the light source group into light beams reduced in a column direction by reducing a line interval of the light beams emitted from the light source group,

the light emitted from each light source of the light source group is parallel light,

the first mirror group is configured such that a plurality of mirrors are arranged in a step-like manner on the optical axis of the light beams emitted from the respective rows of the light source group,

the mirrors are arranged to have the same inclination and are arranged so as to cancel the mutual intervals of the reflected lights from the mirrors.

2. The light source unit according to claim 1, wherein:

the first reflector group is composed of rectangular reflectors, the number of the rectangular reflectors is the same as the number of rows of the light sources in the light source group,

each reflector is arranged parallel to the row direction of the light source group.

3. The light source unit according to claim 1, wherein:

the first reflector group is composed of reflectors with the same number as the light sources in the light source group.

4. The light source unit according to claim 1, wherein:

the light source device includes a second mirror group arranged on an optical axis of the light beam reflected by the first mirror group, and configured to reflect the light beam emitted from the light source into a light beam having a reduced cross-sectional area in a row direction via the first mirror group by reducing a column interval of the light beam emitted from the light source in each column constituting the light source group.

5. The light source unit according to claim 4, wherein:

the second reflecting mirror group is configured such that different rectangular reflecting mirrors are arranged in a step-like manner on the optical axis of the light beam emitted from each row of the light source group and reflected by the first reflecting mirror group,

the mirrors are arranged to cancel the mutual spacing of the reflected light from the mirrors.

6. The light source unit according to claim 1, wherein:

the light source is formed by combining a light emitting element and a collimator lens that converts light emitted from the light emitting element into parallel light.

7. A light source device is provided with:

the light source unit according to any one of claims 1 to 6;

a light-emitting wheel disposed on an optical axis of the light beam emitted from the light source unit;

a wheel motor for rotationally driving the light emitting wheel; and

a single-color light-emitting element having a plurality of light-emitting elements,

the light source device further includes a condensing optical system for condensing the light beam emitted from the light-emitting wheel on a predetermined surface so that the optical axis of the light beam coincides with the optical axis of the light beam emitted from the single-color light-emitting element,

the light emitting wheel is provided with at least a diffusion transmission region for diffusing light emitted from the light source unit and a fluorescence reflection region provided with a fluorescent material for emitting light of a predetermined wavelength band, which are arranged in parallel in a circumferential direction.

8. The light source device according to claim 7, wherein:

the light emitting element of the light source unit is a blue laser emitter,

the fluorescent body in the fluorescence reflection area is a green fluorescent body;

the single-color light emitting element is a red light emitting diode.

9. A projector is provided with:

the light source device according to claim 7;

a light guide device;

a light source side optical system;

a display element;

a projection side optical system; and

a control unit for the projector, the control unit for the projector,

the light-condensing optical system of the light source device condenses the light source light on the incident surface of the light guide device.

10. A projector is provided with:

the light source device according to claim 8;

a light guide device;

a light source side optical system;

a display element;

a projection side optical system; and

a control unit for the projector, the control unit for the projector,

the light-condensing optical system of the light source device condenses the light source light on the incident surface of the light guide device.