JP2005218984A - Film forming method, droplet discharge device, electro-optical device, and electronic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a droplet discharge device capable of reducing data and capable of efficiently forming a high-definition film.
When a droplet discharge nozzle reaches one end of a pixel region, a counter 210 that outputs a trigger signal TR and an input of the trigger signal TR, the droplet discharge signal DS is sent to each droplet discharge nozzle. A waveform file 206 that is uniformly output to the DOT pattern 202 that receives an input of the trigger signal TR and outputs an operation selection signal SC for each droplet discharge nozzle in the pixel region individually to each droplet discharge nozzle. Have.
[Selection] Figure 7

Description

  The present invention relates to a film forming method, a droplet discharge device, an electro-optical device, and an electronic apparatus.

  A method of forming various coatings in a pixel region of an electro-optical device using an ink jet method is known. The ink jet method is a method in which droplets are discharged to a film formation region, and the discharged droplets are wetted and spread over the entire film formation region, and then dried to form a film. As a film forming method using an inkjet method, for example, a method of forming light emitting portions arranged in a matrix in a matrix type display device or a method of forming a filter element of a color filter substrate is known (for example, Patent Document 1).

In general, a droplet discharge device includes a droplet discharge head (hereinafter simply referred to as a head), and a plurality of droplet discharge nozzles are arranged in the head.
FIG. 16 is an explanatory diagram of various signals in the conventional droplet discharge device. When the droplet P is ejected to the rectangular pixel region 6 shown in FIG. 16A, the nozzle row A1 of the head 114 is arranged in parallel with the short side direction of the pixel region 6, and the long side of the pixel region 6 The head 114 is scanned along the direction, and droplets are ejected from the droplet ejection nozzle N1. In this droplet discharge device, a trigger signal shown in FIG. 16B is generated every time the head 114 moves by a predetermined distance with respect to the pixel region 6. The predetermined distance is, for example, a droplet discharge interval. Further, based on each trigger signal, a droplet discharge waveform W shown in FIG. 16C is output. Thereby, the head drive signal DS is generated.

Incidentally, the nozzle N1 shown in FIG. 16A discharges droplets to the pixel regions 6a and 6b, but does not discharge droplets to the intermediate region 7. Therefore, the selection signal SC shown in FIG. 16D is output to the nozzle N1. The selection signal SC includes data for controlling on / off of the nozzles corresponding to each trigger signal. Then, by superposing the selection signal SC of FIG. 16D on the head drive signal DS of FIG. 16C, the ejection waveform ES shown in FIG. 16E is output to the nozzle N1 of the head 114. . As a result, as shown in FIG. 16A, droplets are ejected to the pixel region 6.
JP 2003-127343 A

However, in the above-described droplet discharge method, data for controlling on / off of each nozzle is prepared and stored in the memory of the droplet discharge device in response to a trigger signal output at each droplet discharge interval. There is a need. The operation of preparing this data for all the nozzles is complicated and requires a large amount of memory.
Further, in the above-described droplet discharge method, it is necessary to narrow the droplet discharge interval in order to form a high-definition film. However, in order to narrow the droplet discharge interval, it is necessary to reduce the moving speed of the head, and there is a problem that the production efficiency is lowered.

The present invention has been made in order to solve the above-described problems, and can reduce data, and can efficiently form a high-definition film and a droplet discharge apparatus The purpose is to provide.
It is another object of the present invention to provide an electro-optical device and an electronic apparatus that are low in cost and excellent in display quality.

In order to achieve the above object, the film forming method of the present invention is configured to move a droplet discharge device having a plurality of droplet discharge nozzles from each droplet discharge nozzle to the region while moving the droplet discharge device relative to the film formation region. A method of forming a film by discharging droplets, wherein when all or a part of the droplet discharge nozzles reach a reference point of the region, the droplets to be discharged in the moving direction of the region An operation selection signal for each droplet discharge nozzle in the region is individually output to each droplet discharge nozzle while uniformly outputting a discharge signal to each droplet discharge nozzle. .
According to this configuration, it is sufficient to prepare an operation selection signal for each droplet discharge nozzle in response to the trigger signal output in units of film formation regions, so that data of the operation selection signal can be reduced. In addition, the droplet discharge density can be controlled by adjusting the number of unit waveforms constituting the discharge waveform without reducing the moving speed of the droplet discharge device. Therefore, a high-definition film can be formed efficiently.

Further, in the droplet discharge device, the droplet discharge nozzles are arranged in alignment, the region is formed in a rectangular shape, and the arrangement direction of the droplet discharge nozzles is parallel to the long side direction of the region. It is desirable that the droplet discharge device is disposed so that the droplet discharge device is relatively moved along the short side direction of the region to discharge the droplet.
According to this configuration, it is not necessary to incline the droplet discharge device so that the pitch of each droplet discharge nozzle matches the pitch in the short side direction of each region. In this case, it is not necessary to reconfigure the droplet discharge device every time the pitch in the short side direction of each region is different, and productivity can be improved.

The region may be a plurality of pixel regions in the liquid crystal display device, and the film may be a color filter constituting the liquid crystal display device.
According to this configuration, the color filter can be formed efficiently. Therefore, a low-cost electro-optical device can be provided.

On the other hand, the liquid droplet ejection apparatus of the present invention moves a liquid droplet ejection apparatus having a plurality of liquid droplet ejection nozzles relative to the liquid droplet ejection area, while dropping liquid droplets from the respective liquid droplet ejection nozzles into the area. A device for discharging, trigger signal output means for outputting a trigger signal when all or a part of each of the droplet discharge nozzles reaches a reference point of the region, and by inputting the trigger signal, The discharge signal output means for uniformly outputting the discharge signal of the droplets to be discharged in the moving direction to each of the droplet discharge nozzles, and the operation of each of the droplet discharge nozzles in the region by the input of the trigger signal And an operation selection signal output means for individually outputting a selection signal to each of the droplet discharge nozzles.
According to this configuration, it is possible to provide a droplet discharge device that can reduce data and can efficiently form a high-definition film.

On the other hand, the electro-optical device of the present invention is manufactured using the film forming method described above.
According to this configuration, it is possible to provide an electro-optical device that is low in cost and excellent in display quality.

On the other hand, an electronic apparatus according to the present invention includes the above-described electro-optical device.
According to this configuration, it is possible to provide an electronic device that is low in cost and excellent in display quality.

  Embodiments of the present invention will be described below with reference to the drawings. In each drawing used for the following description, the scale of each member is appropriately changed to make each member a recognizable size.

[Droplet discharge device]
(A. Overall configuration of droplet discharge device)
FIG. 1 is an explanatory diagram of the overall configuration of the droplet discharge device. The ink jet device (droplet discharge device) 100 includes a tank 101 that stores ink (liquid material) 111 and a discharge scanning unit 102 that discharges the ink 111 onto the substrate 70.

  The discharge scanning unit 102 includes a carriage 103 having a plurality of heads, a first position control unit 104 that controls the position of the carriage 103, a stage 106 that can hold a substrate 70 that is a discharge target, and the position of the stage 106. A second position control means 108 for controlling the control and a control unit 112. It should be noted that the ink 111 is supplied from the tank 101 through the pipe 110 to the plurality of heads 114 (see FIG. 2) provided on the carriage 103.

  As shown in FIG. 1, the carriage 103 is configured to be movable in the X-axis direction by the first position control means 104, and the stage 106 is configured to be movable in the Y-axis direction by the second position control means 108. That is, the relative position of the head 114 with respect to the stage 106 can be changed by the first position control means 104 and the second position control means 108. That is, the carriage 103 and the stage 106 can move relatively, that is, relatively scan in the X-axis direction and the Y-axis direction while maintaining a predetermined distance in the Z-axis direction. The carriage 103 and the stage 106 further have degrees of freedom of parallel movement and rotation other than those described above. However, in order to facilitate understanding, explanations regarding degrees of freedom other than the above degrees of freedom are omitted.

(B. Carriage)
FIG. 2 is a bottom view of the carriage 103 observed from the stage side, and the direction perpendicular to the paper surface of FIG. 2 is the Z-axis direction. In FIG. 2, the horizontal direction on the paper is the X-axis direction, and the vertical direction on the paper is the Y-axis direction. The carriage 103 is provided with a plurality of heads 114 each having substantially the same structure. In the present embodiment, the number of heads 114 held by the carriage 103 is 24. The bottom surface of each head 114 has a substantially rectangular shape, and the long side direction and the short side direction are arranged in parallel with the X-axis direction and the Y-axis direction, respectively. The bottom surface of each head 114 is arranged toward the stage side. The relative positional relationship between the heads 114 in the carriage 103 will be described later.

(C. Head)
FIG. 3 shows the bottom structure of the head 114. A plurality of nozzles 118 are formed on the bottom surface of the head 114 as ink ejection openings. In the present embodiment, 180 nozzles 118 are arranged at regular intervals HXP. The nozzles 118 are arranged in a staggered manner along the X-axis direction, and a nozzle row 1A and a nozzle row 1B are configured. In each of the nozzle rows 1A and 1B, 90 nozzles 118 are arranged at a constant interval LNP. However, several nozzles at both ends of each of the nozzle arrays 1A and 1B are set as “pause nozzles” where ink is not discharged, and the other nozzles are set as “discharge nozzles” where ink is discharged.

  4A is a perspective view showing the configuration of the ejection portion of the head 114, and FIG. 4B is a side sectional view taken along line BB of FIG. 4A. As shown in FIG. 4A, a nozzle plate 128 on which the nozzles 118 are formed is disposed on the bottom surface of the head 114. A plurality of cavities 120 are formed between the nozzle plate 128 and the diaphragm 126 so as to correspond to the nozzles 118. Ink is supplied from the tank 101 shown in FIG. 1 to each cavity 120 via the hole 131 and the supply port 130 shown in FIG.

  On the other hand, on the outside of the diaphragm 126, a plurality of vibrators 124 are disposed corresponding to the cavities 120. As shown in FIG. 4B, the vibrator 124 is configured by sandwiching a piezo element 124C between a pair of electrodes 124A and 124B. When a drive voltage is applied to the pair of electrodes 124A and 124B from the control unit 112 shown in FIG. 1, the piezoelectric element 124C shown in FIG. 4B mechanically vibrates due to the piezoelectric effect. As a result, the internal pressure of the cavity 120 varies and the ink 111 is ejected from the nozzle 118. An electrothermal conversion element can be employed instead of the piezo element. In this specification, a portion including one nozzle 118, a cavity 120 corresponding to the nozzle 118, and a vibrator 124 corresponding to the cavity 120 may be referred to as “ejection unit 127”.

(D. Head group)
FIG. 5 is a schematic diagram showing the relative positional relationship between the heads in the carriage. FIG. 5 shows two adjacent head groups 114G among the plurality of head groups 114G shown in FIG. In addition, in each head group 114G shown in FIG. 5, four heads 114 (1141, 1142, 1143, 1144) are arranged in a staircase pattern. In the present embodiment, the product of the nozzle pitch HXP in the X-axis direction of the head 114 and the number of ejection nozzles in the head 114 is referred to as “effective head length HL”. In this embodiment, four sub-regions SR (SR1, SR2, SR3, SR4) continuous in the X-axis direction are set for each head 114. The length DL in the X-axis direction in each sub-region SR is 1/4 times the effective head length HL.

  In the present embodiment, the leftmost discharge nozzle among the plurality of discharge nozzles in each head 114 is defined as a “reference nozzle 118R”. Each head 114 constituting the head group 114G is arranged so that the X coordinate of the reference nozzle 118R of the adjacent head 114 is shifted by DL + HXP / 2 with respect to the X coordinate of the reference nozzle 118R of each head 114. . As a result, the X coordinates of the four nozzles are within the range of the length of the nozzle pitch HXP along the X-axis direction. In the present embodiment, this portion is referred to as a superimposed portion G (G1 to G7 in FIG. 5). For example, the overlapping portion G1 includes a nozzle N1 in the nozzle row 1A, a nozzle N2 in the nozzle row 2A, a nozzle N3 in the nozzle row 3A, and a nozzle N4 in the nozzle row 4A. As a result, the nozzle pitch GXP in the X-axis direction in the entire head group 114G is ¼ times the nozzle pitch HXP in the X-axis direction in each head 114.

  And according to the head arrangement of this embodiment, nozzles belonging to the sub-regions SR1 to SR4 are included in any of the overlapping portions G1 to G7. In addition, the number of nozzles in each sub-region included in one overlapping portion (for example, the overlapping portion G1) is the same.

  FIG. 6A is a graph schematically showing a discharge amount profile in one head 114 along the X-axis direction. In the general head 114, the discharge amount from the nozzles at both ends is the largest, and the discharge amount from the substantially central nozzle is the smallest. The reason is due to a manufacturing problem of the head 114, but detailed description thereof is omitted here.

  FIG. 6B is a graph schematically showing a discharge amount profile of each of the overlapping portions G1 to G7 in the head group along the X-axis direction. As described above, in the head configuration in the present embodiment, the overlapping portions G1 to G7 are configured by nozzles belonging to different sub-regions. For this reason, the total volume of the liquid droplets ejected from the overlapping portions G1 to G7 is almost the same. Accordingly, the difference in the discharge amount is less likely to appear in the row of droplets discharged from the head group, and a uniform film can be formed.

  On the other hand, in the superimposition part G1 shown in FIG. 5, each nozzle is arrange | positioned as follows. That is, the X coordinate of the nozzle N2 in the nozzle row 2A substantially matches the middle of the X coordinate of the nozzle N1 in the nozzle row 1A and the X coordinate of the nozzle N5 in the nozzle row 1B. Further, the X coordinate of the nozzle N3 in the nozzle row 3A substantially matches the middle of the X coordinate of the nozzle N1 in the nozzle row 1A and the X coordinate of the nozzle N2 in the nozzle row 2A. Furthermore, the X coordinate of the nozzle N4 in the nozzle row 4A is substantially coincident with the X coordinate of the nozzle N5 in the nozzle row 1B and the X coordinate of the nozzle N3 in the nozzle row 2A.

  In order to discharge ink to the rectangular discharge target area 18L, the long side direction of the discharge target area 18L and the nozzle row of each head 114 are arranged substantially in parallel, and the short side direction of the discharge target area 18L. The head group 114G is moved relative to the head. Then, ink is sequentially discharged from the nozzle row that reaches the upper side of the discharge target region 18L. For example, in the overlapping portion G1, the droplet P1 is first ejected from the nozzle N1 in the nozzle row 1A, and then the droplet P5 is ejected from the nozzle N5 in the nozzle row 1B. Next, the droplet P2 is ejected from the nozzle N2 in the nozzle row 2A substantially between the droplet P1 and the droplet P5. Next, the droplet P3 is ejected from the nozzle N3 in the nozzle row 3A approximately in the middle between the droplet P1 and the droplet P2. Next, the droplet P4 is ejected from the nozzle N4 in the nozzle row 4A substantially between the droplet P5 and the droplet P2.

  As described above, according to the head configuration of the present embodiment, the next droplet lands in the middle of the two droplets that have landed first. For this reason, a force acts in a symmetric direction on the droplets that have landed later from the two droplets that have landed earlier. As a result, the liquid droplets that have landed later spread in a symmetrical shape from the landing position. Therefore, according to the ejection method of the present embodiment, the liquid material is less likely to be unevenly applied, and a uniform film can be formed.

  Further, according to the head configuration of the present embodiment, the nozzle rows are arranged in a direction (X-axis direction) orthogonal to the direction (Y-axis direction) in which the head group 114 </ b> G relatively moves. For this reason, ink can be ejected from the nozzles constituting the nozzle row substantially simultaneously to the ejection target region 18L extending in the X-axis direction. As a result, the DOT pattern 202 shown in FIG. 7 only needs to output one type of drive signal DS to each nozzle row, and a circuit configuration for delaying the drive signal DS is not necessary. Thereby, there are few factors that cause the waveform in the drive signal DS to be rounded, and a precise ejection waveform can be applied to the vibrator. Therefore, ink can be stably ejected from each nozzle.

  Furthermore, according to the head configuration of the present embodiment shown in FIG. 5, the nozzle pitch GXP in the X-axis direction in the head group 114G is 1 / N times as long as the nozzle pitch HXP in the X-axis direction in each head 114. . Here, N is the number of heads 114 included in the head group 114G. For this reason, the nozzle line density in the X-axis direction in the droplet discharge device of the present embodiment is N times the nozzle line density in the X-axis direction in the conventional droplet discharge device. Therefore, a more precise landing pattern can be formed along the X-axis direction within a period in which the head group 114G is relatively moved only once in the Y-axis direction.

  In the conventional droplet discharge device, the head is arranged so that the short side direction of the rectangular discharge region and the nozzle row are substantially parallel, and the head is moved along the long side direction of the discharge region. As a result, droplets were discharged to the discharge target region. Further, when ejecting droplets to a plurality of ejection target areas arranged in parallel, the heads are inclined so as to match the pitch of each nozzle with the pitch in the short side direction of each ejection area. On the other hand, in the head configuration of the present embodiment, the head is arranged so that the long side direction of the discharge target region and the nozzle row are substantially parallel, and the head is moved along the short side direction of the discharge target region. As a result, droplets are discharged to the discharge target region. This eliminates the need for the head to be inclined and eliminates the need to reconfigure the head every time the pitch of the ejected area is different. Therefore, productivity can be improved.

(E. Control part)
FIG. 7 is a block diagram illustrating a configuration of the control unit. The control unit 112 includes a counter 210 that outputs a trigger signal, a waveform file 206 that outputs a discharge waveform, a DOT pattern 202 that outputs a selection signal, a CPU 204 that performs arithmetic processing, and a drive circuit 208 that outputs a drive signal for the head 114. , Connected to the bus 200.

  The counter 210 is connected to a linear scale 211 that detects the relative position between the carriage and the stage. When the linear scale 211 detects that the nozzle row formed in each head of the carriage has reached the reference point of the discharge area on the substrate on the stage, the counter 210 outputs a trigger signal. ing.

On the other hand, the waveform file 206 stores the input ejection waveform W, and can output the ejection waveform W according to the trigger signal. This discharge waveform W is configured by combining a plurality of unit waveforms V for discharging one droplet.
The DOT pattern 202 stores an input operation selection signal (hereinafter simply referred to as a selection signal) SC and can output the selection signal SC in accordance with a trigger signal. The selection signal SC is composed of data for controlling on / off of nozzles, and is prepared for all nozzles formed on the carriage.

  FIG. 8A is a block diagram showing the configuration of the drive circuit. A driving circuit 208 shown in FIG. 8A is provided with a plurality of analog switches AS corresponding to the respective vibrators 124 of the head. A drive signal DS is uniformly input to each analog switch AS. In addition, the selection signal SC (SC1, SC2,...) Is individually input to each analog switch AS.

  FIG. 8B is a timing chart of various signals. The waveform file described above outputs the ejection waveform W in response to the trigger signal TR, and outputs the reference potential L in other time zones. As a result, the drive signal DS is output from the waveform file. This discharge waveform W corresponds to a drive voltage waveform to be applied between a pair of electrodes in the vibrator in order to discharge a droplet from the nozzle.

  Note that the volume of the droplets ejected from the head is controlled by the ejection waveform W. Therefore, data of a discharge waveform W that can discharge a predetermined volume of droplets is input to the waveform file. However, a necessary droplet volume may be input to the drive signal generation unit, and the drive signal generation unit may generate the ejection waveform W from the data. In this case, a correlation table between the droplet volume and the discharge waveform W is input in advance to the waveform file. According to this configuration, the amount of data input to the waveform file can be reduced.

  On the other hand, a plurality of selection signals SC (SC1, SC2,...) For controlling on / off of each nozzle are supplied to each analog switch AS shown in FIG. The selection signal SC shown in FIG. 8B can take either a high level or a low level for each trigger signal. Each analog switch AS shown in FIG. 8A supplies an ejection signal ES (ES1, ES2,...) To one electrode of the vibrator 124 in accordance with the drive signal DS and the selection signal SC. As shown in FIG. 8B, when the selection signal SC is at a high level, the drive signal DS is supplied as the ejection signal ES. On the other hand, when the selection signal SC is at a low level, the reference potential L is supplied as the ejection signal ES. 8A, since the reference potential L is applied to the other electrode of the vibrator 124, when the drive signal DS is applied to one electrode of the vibrator 124, the vibrator Ink is ejected from nozzles corresponding to 124.

[Film Formation Method]
In the present embodiment, a method for forming a color filter film of an electro-optical device using the above-described droplet discharge device will be described.
9 is a plan view of the color filter, and is a cross-sectional view taken along the line CC of FIG. The color filters 22R, 22G, and 22B shown in FIG. 9 are formed in a rectangular shape by pigments that transmit different color lights (RGB). Each color filter is arranged in a matrix on the transparent substrate corresponding to the plurality of pixel regions 6 in the electro-optical device. A light shielding film 77 is formed on the peripheral edge of each color filter. In order to form the color filter film 22 by the ink jet method, first, an ink is prepared by dispersing a pigment or the like in a dispersion medium. Next, using the above-described droplet discharge device, ink is discharged into the pixel region 6 partitioned by the light shielding film 77. Then, after the discharged ink has spread over the entire pixel region 6, the ink is dried and the color filter film 22 is baked.

  FIG. 10A is a plan view of droplets ejected into the pixel area. In the present embodiment, a plurality of droplets are ejected in the short side direction of the pixel region 6G. In the pixel region 6G shown in FIG. 10A, droplets P are arranged in a matrix of 9 rows × 3 columns in the long side direction × short side direction.

Here, a method of arranging the droplets as shown in FIG. 10A will be described with reference to FIGS.
First, as shown in FIG. 10A, the carriage 103 described above is arranged so that the arrangement direction of the nozzle rows in the head 114 is parallel to the long side direction of the pixel region 6G. Next, the carriage 103 is moved along the short side direction of the pixel region 6G. Then, when the nozzle row of the head 114 reaches above the pixel region 6G, a droplet is ejected from a predetermined nozzle to a predetermined position. Each droplet may be ejected so as to partially overlap with an adjacent droplet, or may be ejected while being separated from each other. In addition, the droplets discharged to the same row in the pixel region 6G may be discharged simultaneously from a plurality of nozzles belonging to the same nozzle row of the same head, or may be discharged sequentially from a plurality of nozzles belonging to different heads. . In the following, in order to facilitate understanding, an example will be described in which ejection is simultaneously performed from a plurality of nozzles belonging to the same nozzle row of the same head.

  FIG. 10B to FIG. 10E are timing charts of various signals for discharging droplets as shown in FIG. When the nozzle row of the head 114 reaches the one end 61 of each pixel region 6R, 6G, 6B, the counter 210 shown in FIG. 7 outputs the trigger signal TR shown in FIG. On the other hand, the waveform file 206 shown in FIG. 7 outputs the head drive signal DS shown in FIG. The discharge waveform W constituting the head drive signal DS is capable of discharging a plurality of droplets from one end 61 to the other end 62 of the pixel region 6G.

On the other hand, the DOT pattern 202 shown in FIG. 7 outputs the selection signal SC shown in FIG. The selection signal SC is high level or low level for each pixel region 6. Specifically, the nozzle row is at a high level during the time zone when it passes through the pixel area 6G, and is at the low level during a time zone when it passes through other areas.
As described above, the discharge signal ESe shown in FIG. 10E is output from the analog switch to the vibrator of the nozzle that discharges droplets to the pixel region 6G shown in FIG. Thereby, a plurality of droplets can be ejected in the short side direction of the pixel region 6G.

  Further, another method for arranging the droplets as shown in FIG. 10A will be described with reference to FIGS. 7, 8, and 11. FIG. FIG. 11A is a plan view of liquid droplets ejected into the pixel area as in FIG.

FIG. 11B to FIG. 11E are timing charts of various signals for discharging droplets as shown in FIG. The trigger signal TR shown in FIG. 11B is generated when the nozzle row of the head 114 reaches the one end 61 of the pixel region 6G, but is not generated in other regions. When the waveform file 206 shown in FIG. 7 outputs the ejection waveform W every time the trigger signal TR is received, the head drive signal DS shown in FIG. 10C is output.
On the other hand, the DOT pattern 202 shown in FIG. 7 outputs the selection signal SC shown in FIG. As a result, the ejection signal ES shown in FIG. 11E is output from the analog switch to the vibrator of the nozzle that ejects droplets to the pixel region 6G shown in FIG. Thereby, a plurality of droplets can be ejected in the short side direction of the pixel region 6G.

  FIG. 12 is a comparison diagram of the data amount of the selection signal. Here, consider a case where droplets are ejected to a plurality of pixel regions 6 shown in FIG. Also in this case, the carriage is arranged so that the long side direction of the pixel region 6 and the nozzle row of the head 114 are parallel, and the carriage is moved along the short side direction of the pixel region 6. Here, the nozzle N1 of the head 114 passes above the pixel region 6, but the nozzle N2 does not pass above the pixel region 6. Therefore, the droplet P is ejected from the nozzle N1 to the pixel region 6, but the droplet is not ejected from the nozzle N2. However, when the nozzle N1 passes between the pixel regions 6a and 6b, no droplets are ejected from the nozzle N1.

  FIG. 12B is an explanatory diagram of the data amount of the selection signal in the conventional droplet discharge method. In the conventional droplet discharge method, the trigger signal TR is generated every time the head and the pixel region move relatively by a predetermined distance. Then, selection signal data is prepared for each trigger signal. The selection signal SC1 corresponding to the nozzle N1 has ON data at a timing (corresponding to the trigger signals T1 to T3 and T5 to T7) when the nozzle N1 passes above the pixel area 6, and the nozzle N1 At the timing of passing between them (corresponding to trigger signals T4 and T8), there is off data. Further, the selection signal SC2 corresponding to the nozzle N2 has OFF data at all timings of the trigger signals T1 to T8. In FIG. 12, ON data is represented by ◯, and OFF data is represented by ×.

  FIG. 12C is an explanatory diagram of the data amount of the selection signal in the droplet discharge method of the present embodiment. In the droplet discharge method of this embodiment, a trigger signal is generated when the nozzle row of the head reaches one end of the pixel region. The ejection waveform output in response to the trigger signal can eject a plurality of droplets from one end to the other end of the pixel region. For this reason, if ON data is prepared for the trigger signal, a droplet is ejected to the entire pixel region and a droplet is not ejected between the pixel regions. Thus, the selection signal SC1 corresponding to the nozzle N1 has ON data at the timing of the trigger signals T1 and T2, and the selection signal SC2 corresponding to the nozzle N2 has OFF data at the timing of the trigger signals T1 and T2. Have.

  As described above, in the droplet discharge method of the present embodiment, the trigger signal is generated when the nozzle row of the head reaches one end of the droplet discharge region, and the data of the selection signal is corresponding to each trigger signal. Since preparation is sufficient, the number of data of the selection signal can be reduced. This makes it possible to reduce the memory capacity of the DOT pattern 202 and reduce the man-hours for data input to the DOT pattern 202 in the droplet discharge device shown in FIG.

Further, when the time interval of the trigger signal becomes longer as described above, the relative movement speed between the carriage and the table can be improved.
In general, the relative movement speed between the carriage and the table is calculated by multiplying the head driving frequency by the droplet discharge interval. In the conventional droplet discharge method, in order to perform high-definition drawing, it is necessary to narrow the droplet discharge interval, which causes a problem that the relative movement speed between the carriage and the table decreases. . On the other hand, in the droplet discharge method of the present embodiment, the droplet discharge density can be controlled by adjusting the number of unit waveforms included in the discharge waveform. In this case, it is not necessary to reduce the relative movement speed between the carriage and the table, and a high-definition film can be formed efficiently.

[Electro-optical device]
The color filter formed as described above constitutes an electro-optical device. Therefore, a schematic configuration of a liquid crystal display device which is an example of an electro-optical device will be described with reference to FIGS. In the present specification, the liquid crystal layer side of each component of the liquid crystal display device is referred to as an inner side.

  13 is an exploded perspective view of the liquid crystal display device, and FIG. 14 is a side sectional view taken along line AA of FIG. As shown in FIG. 14, the liquid crystal display device 1 is configured by sandwiching the liquid crystal layer 2 between a lower substrate 70 and an upper substrate 80. A nematic liquid crystal or the like is employed for the liquid crystal layer 2, and a twisted nematic (TN) mode is employed as an operation mode of the liquid crystal display device 1. Note that liquid crystal materials other than those described above can be employed, and operation modes other than those described above can be employed. Hereinafter, an active matrix type liquid crystal display device using a TFD element as a switching element will be described as an example. However, the present invention is applied to other active matrix type liquid crystal display devices and passive matrix type liquid crystal display devices. It is also possible to apply.

As shown in FIG. 13, in the liquid crystal display device 1, a lower substrate 70 and an upper substrate 80 made of a transparent material such as glass are disposed to face each other.
A plurality of data lines 81 are formed inside the upper substrate 80. A plurality of pixel electrodes 82 made of a transparent conductive material such as ITO are arranged in a matrix on the side of the data line 81. Note that a pixel region is constituted by the formation region of each pixel electrode 82. The pixel electrode 82 is connected to each data line 81 via the TFD element 83. The TFD element 83 includes a first conductive film mainly composed of Ta formed on the surface of the substrate, an insulating film mainly composed of Ta ₂ O ₃ formed on the surface of the first conductive film, and an insulation thereof. A second conductive film mainly composed of Cr formed on the surface of the film (so-called MIM structure). The first conductive film is connected to the data line 81 and the second conductive film is connected to the pixel electrode 82. Accordingly, the TFD element 83 functions as a switching element that controls energization to the pixel electrode 82.

  On the other hand, the color filter film 22 is formed inside the lower substrate 70 as described above. The color filter film 22 is configured by color filters 22R, 22G, and 22B having a substantially rectangular shape in plan view. Each of the color filters 22R, 22G, and 22B is composed of a pigment that transmits only different color light, and is arranged in a matrix corresponding to each pixel region. Further, in order to prevent light leakage from adjacent pixel regions, a light shielding film 77 is formed on the peripheral edge of each color filter. The light shielding film 77 is formed in a frame shape from black metal chrome having light absorptivity. Further, a transparent insulating film 79 is formed so as to cover the color filter film 22 and the light shielding film 77.

  A plurality of scanning lines 72 are formed inside the insulating film 79. The scanning line 72 is formed in a substantially strip shape by a transparent conductive material such as ITO and extends in a direction intersecting the data line 81 of the upper substrate 80. The scanning line 72 is formed so as to cover the color filters 22R, 22G, and 22B arranged in the extending direction, and functions as a counter electrode. When a scanning signal is supplied to the scanning line 72 and a data signal is supplied to the data line 81, an electric field is applied to the liquid crystal layer by the opposing pixel electrode 82 and the opposing electrode 72.

  Further, as shown in FIG. 14, alignment films 74 and 84 are formed so as to cover the pixel electrode 82 and the counter electrode 72. The alignment films 74 and 84 control the alignment state of the liquid crystal molecules when no electric field is applied, and are made of an organic polymer material such as polyimide, and the surface thereof is rubbed. As a result, when no electric field is applied, the liquid crystal molecules in the vicinity of the surfaces of the alignment films 74 and 84 are aligned substantially parallel to the alignment films 74 and 84 with the major axis direction coinciding with the rubbing treatment direction. . The alignment films 74 and 84 are rubbed so that the alignment direction of the liquid crystal molecules near the surface of the alignment film 74 and the alignment direction of the liquid crystal molecules near the surface of the alignment film 84 are shifted by a predetermined angle. It has been subjected. Thus, the liquid crystal molecules constituting the liquid crystal layer 2 are stacked in a spiral shape along the thickness direction of the liquid crystal layer 2.

Further, the peripheral portions of the substrates 70 and 80 are joined by a sealing material 3 made of an adhesive such as a thermosetting type or an ultraviolet curable type. The liquid crystal layer 2 is sealed in a space surrounded by the substrates 70 and 80 and the sealing material 3. Note that the thickness (cell gap) of the liquid crystal layer 2 is regulated by the spacer particles 5 disposed between the two substrates.
On the other hand, a polarizing plate (not shown) is disposed outside the lower substrate 70 and the upper substrate 80. Each polarizing plate is arranged in a state in which the mutual polarization axes (transmission axes) are shifted by a predetermined angle. Further, a backlight (not shown) is disposed outside the incident side polarizing plate.

The light emitted from the backlight is converted into linearly polarized light along the polarization axis of the incident-side polarizing plate, and enters the liquid crystal layer 2 from the lower substrate 70. This linearly polarized light is rotated by a predetermined angle along the twist direction of the liquid crystal molecules in the process of passing through the liquid crystal layer 2 in a state where no electric field is applied, and is transmitted through the output side polarizing plate. Thereby, white display is performed when no electric field is applied (normally white mode). On the other hand, when an electric field is applied to the liquid crystal layer 2, the liquid crystal molecules are reoriented perpendicularly to the alignment films 74 and 84 along the electric field direction. In this case, since the linearly polarized light incident on the liquid crystal layer 2 does not rotate, it does not pass through the output side polarizing plate. Thereby, black display is performed when no electric field is applied. Note that gradation display can also be performed depending on the strength of an applied electric field.
The liquid crystal display device 1 is configured as described above.

[Electronics]
FIG. 15 is a perspective view showing an example of an electronic apparatus according to the invention. A cellular phone 1300 shown in the figure includes the above-described electro-optical device as a small-sized display unit 1301 and includes a plurality of operation buttons 1302, a mouthpiece 1303, and a mouthpiece 1304.
The above-described electro-optical device is not limited to the above mobile phone, but an electronic book, a personal computer, a digital still camera, a liquid crystal television, a viewfinder type or a monitor direct-view type video tape recorder, a car navigation device, a pager, an electronic notebook, a calculator, It can be suitably used as an image display means for a word processor, a workstation, a videophone, a POS terminal, a device equipped with a touch panel, etc. In any case, an electronic device with excellent display quality can be provided at low cost. .

  The technical scope of the present invention is not limited to the above-described embodiments, and includes those in which various modifications are made to the above-described embodiments without departing from the spirit of the present invention. That is, the specific materials and configurations described in the embodiments are merely examples, and can be changed as appropriate. For example, in the above-described embodiment, the head is disposed so that the long side direction of the discharge target region and the nozzle row are substantially parallel, and the head is moved along the short side direction of the discharge target region. The method for discharging droplets to the region has been described. On the other hand, the head is arranged so that the short side direction of the rectangular discharge region and the nozzle row are substantially parallel, and the head is moved along the long side direction of the discharge region. It is also possible to carry out the film forming method of the present invention by using a method of discharging droplets to the region.

It is explanatory drawing of the whole structure of a droplet discharge apparatus. It is the bottom view which observed the carriage from the stage side. It is a bottom face lineblock diagram of a head. (A) is a perspective view which shows the structure of the discharge part of a head, (b) is side sectional drawing in the BB line of (a). It is a schematic diagram which shows the relative positional relationship of each head in a carriage. (A) is a graph which shows the profile of the discharge amount in one head, (b) is a graph which shows the profile of the discharge amount of each superimposition part in a head group. It is a block diagram which shows the structure of a control part. (A) is a block diagram showing a configuration of a head driving unit, (b) is a timing chart of various signals in the head driving unit. It is a top view of a color filter. (A) is a top view of the droplet discharged to the pixel area, and (b) to (e) are timing charts of various signals. (A) is a top view of the droplet discharged to the pixel area, and (b) to (e) are timing charts of various signals. It is a comparison figure of the data amount of a selection signal. It is a disassembled perspective view of a liquid crystal display device. It is side surface sectional drawing of a liquid crystal display device. It is a perspective view of the mobile phone which shows an example of an electronic device. (A) is a top view of the droplet discharged to the pixel area, and (b) to (e) are timing charts of various signals.

Explanation of symbols

  SC operation selection signal TR trigger signal DS discharge signal 202 DOT pattern 206 waveform file 210 counter

Claims (6)

A method of forming a film by discharging droplets from each droplet discharge nozzle to the region while moving a droplet discharge device including a plurality of droplet discharge nozzles relative to the film formation region,
When all or part of the droplet discharge nozzles reach the reference point of the region, a droplet discharge signal to be discharged in the moving direction of the region is uniformly output to each droplet discharge nozzle. However, the film forming method is characterized in that an operation selection signal for each droplet discharge nozzle in the region is individually output to each droplet discharge nozzle. In the droplet discharge device, the droplet discharge nozzles are aligned and arranged,
The region is formed in a rectangular shape,
The droplet discharge device is arranged so that the arrangement direction of the droplet discharge nozzles is parallel to the long side direction of the region, and the droplet discharge device is relatively moved along the short side direction of the region. The film forming method according to claim 1, wherein the droplets are discharged. The region is a plurality of pixel regions in a liquid crystal display device,
The film forming method according to claim 1, wherein the film is a color filter constituting a liquid crystal display device. A device that discharges droplets from each droplet discharge nozzle to the region while moving a droplet discharge device including a plurality of droplet discharge nozzles relative to the droplet discharge region,
Trigger signal output means for outputting a trigger signal when all or a part of each droplet discharge nozzle reaches a reference point of the region;
Discharge signal output means for uniformly outputting a discharge signal of droplets to be discharged in the moving direction of the region to each of the droplet discharge nozzles by inputting the trigger signal;
An operation selection signal output means for individually outputting an operation selection signal of each droplet discharge nozzle in the region to each droplet discharge nozzle by the input of the trigger signal;
A droplet discharge apparatus comprising: An electro-optical device manufactured using the film forming method according to claim 1. An electronic apparatus comprising the electro-optical device according to claim 5.

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