JP2009288349A - Discharge lamp lighting device and image display device using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a discharge lamp lighting device which is improved in color representation performance by reducing time shift of timing even though the number of times of setting synchronism between switching timing and the output timing of a color segment is reduced. <P>SOLUTION: The discharge lamp lighting device 101 includes a lighting circuit (converter circuit 1 and inverter circuit 2) for lighting a high-voltage discharge lamp La, and a control circuit 5 for controlling an output from the lighting circuit to the high-voltage discharge lamp La for each color segment. The control circuit 5 includes a timing signal input circuit 5d for obtaining a timing signal inputted for each rotation of the color segment, and a segment time calculation processing part 6d for obtaining an incident period of time from reception of the timing signal to entry of a luminous flux to each color segment, wherein the output from the lighting circuit to the high-voltage discharge lamp La is controlled according to the color segment, at the passage point of time of the incident time to each segment from the input time of the timing signal. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a discharge lamp lighting device and an image display device used for an image display device.

  2. Description of the Related Art Conventionally, there has been provided an image display device using a reflective optical element called DMD (registered trademark) (Digital Micromirror Device). FIG. 15 is a schematic configuration diagram of such an image display device, which is a discharge lamp lighting device 101 for lighting a high-pressure discharge lamp La as a light source, and is divided into a plurality of color segments 103a that are disk-shaped and rotated in the rotation direction. The color filter 103 in which the light beam emitted from the high-pressure discharge lamp La by rotating at a constant speed is sequentially incident on each color segment 103a, and the lens for condensing the irradiation light from the high-pressure discharge lamp La on the color filter 103 104, a lens 105 for condensing light that has passed through the color filter 103 on an optical element 106, which will be described later, and a DMD (registration) that applies gradation to the luminous flux of each color that has passed through the lens 105 and modulation by a video signal. (Trademark) (Digital Micromirror Device) A reflective optical element 106 and the light reflected by the optical element 106 are projected. A projection lens 107 to be projected onto the projector, and an image display control circuit 102 that controls the rotation of the color filter 103 and controls the light output of the high-pressure discharge lamp La in accordance with the color segment 103a on which the lamp luminous flux is incident. . In addition, the arrow in a figure has shown the lamp | ramp light beam irradiated from a high pressure discharge lamp.

  In the conventional image display device, in order to improve the brightness, the color filter 103 is white (W: W) in addition to the three primary colors of red (R: red), green (G: green), and blue (B: blue). white) color segment 103a is provided. However, the addition of the white color segment 103a reduces the resolution of red, green, and blue, resulting in a problem in that the color saturation performance deteriorates. Therefore, in order to improve the performance of color saturation, in addition to R, G, B, and W, secondary colors such as cyan (C: cyan), magenta (M: magenta), and yellow (Y: yellow) are used. A technique (so-called brilliant color technique) that improves the color saturation by providing the segment 103a and increasing the luminance of the complementary color has been proposed.

  Further, as described in Patent Document 1, for example, by controlling the lighting power and lamp current supplied to the high-pressure discharge lamp, a plurality of color filters are realized in a pseudo manner using one color filter (color wheel) and used. By realizing color filters according to the application (for example, a theater mode suitable for watching movies, an image mode such as a presentation mode suitable for displaying presentation materials for presentations), it can be expressed in colors suitable for the intended use. Such variable illumination technology has been adopted.

  In the discharge lamp lighting device used for such an image display device, the discharge lamp lighting device can express a color suitable for each image mode. Therefore, there is a need for a technique for instantaneously controlling the lamp power waveform or the lamp current waveform for each color segment of the power Luller filter.

  In order to express a color suitable for each image mode as described above, when the lamp power or lamp current is controlled for each color segment, the timing at which the color segment switches and the lamp power waveform corresponding to the color segment or It is necessary to match the change timing of the lamp power waveform or the lamp current waveform so that there is no time lag from the change timing of the lamp current waveform. Here, if there is a discrepancy between the switching timing of the color segment and the timing at which the lamp power waveform or the lamp current waveform changes, it becomes impossible to input an appropriate lamp power or lamp current in that color segment, resulting in the intensity of light east. In addition, there is a problem that the color expression performance in the color segment is deteriorated.

In order to reduce such a timing shift, for example, in the image display device disclosed in Patent Document 2, the timing is adjusted between the image display device and the discharge lamp lighting device every time the color segment is switched.
JP 2006-189485 A JP 2007-79330 A

  In the image display device disclosed in Patent Document 2 described above, the timing is synchronized between the image display device and the discharge lamp lighting device every time the color segment is switched. There was a problem of becoming complicated.

  In a circuit in which a discharge lamp lighting device receives a timing signal from an image display device, signals are generally exchanged through a photocoupler in order to electrically insulate the devices from each other, as shown in FIG. Since the signal waveform of the secondary-side output signal CS1 is dull when the primary-side signal CS0 of the photocoupler is turned off, there is a time lag from when the input signal CS0 switches off until the output signal CS1 exceeds the threshold level. When Δt is generated and the off-time signal is used as the timing signal, there is a problem that the time deviation becomes large and the color expression performance is deteriorated.

  The present invention has been made in view of the above problems, and the object of the present invention is to reduce the time deviation of the timing while the number of times of synchronizing the color segment switching timing and the output switching timing is small. It is another object of the present invention to provide a discharge lamp lighting device with improved color expression performance and an image display device using the same.

  In order to achieve the above object, a first aspect of the present invention is a color filter that is divided into color segments of a plurality of colors in the rotation direction, and a light beam emitted from a high-pressure discharge lamp is sequentially incident on each color segment according to the rotation. And a discharge lamp lighting device for use in an image display device including a video display element that performs gradation and modulation by a video signal on each color beam that has passed through a color filter, and is a lamp that lights a high-pressure discharge lamp. And a control circuit for controlling the output from the lighting circuit to the high-pressure discharge lamp for each color segment. The control circuit receives a timing signal output from the image display device for each cycle of the color segment. Based on the timing signal input means and the time interval at which the timing signal is input, the luminous flux enters each color segment from the time the timing signal is received. Segment incident time detecting means for determining the incident time until the high voltage discharge lamp from the lighting circuit at the time when the incident time to each segment detected by the segment incident time detecting means has elapsed from the input timing of the timing signal. The output to is controlled in accordance with the color segment.

  According to a second aspect of the present invention, in the first aspect of the invention, the segment incident time detecting means is configured to determine the incident time to each color segment in the next period based on a time interval for one period in which the timing signal is input. Is detected.

  According to a third aspect of the present invention, in the first aspect of the present invention, the segment incident time detection means is configured to determine the incident time to each color segment in the next period based on the time intervals for a plurality of periods in which the timing signal is input. Is detected.

  According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, when the timing signal is input while the light beam is incident on the color segment at the beginning of one cycle, the control circuit performs the timing. Based on the result of detecting the time width of the signal, it is detected whether or not the rotation speed of the color filter has changed. When the rotation speed has changed, the detection result of the time width and the ratio of the rotation angle of each color segment The incident time of each color segment is calculated based on the above.

  According to a fifth aspect of the present invention, in any one of the first to fourth aspects of the present invention, the time of one cycle in which the timing signal is input is 1 mS or more and 100 mS or less.

  The invention of claim 6 is the invention of any one of claims 1 to 5, wherein the color filter has at least a white color segment, and the timing at which the timing signal is input is at the end of the white color segment. It is characterized by being.

  A seventh aspect of the present invention is an image display device, comprising: the discharge lamp lighting device according to any one of the first to sixth aspects for lighting a high pressure discharge lamp; and the high pressure discharge lamp having a plurality of color segments. A color filter in which the irradiated light beam is sequentially incident on each segment, and a video display element that performs gradation and modulation by a video signal on each color light beam that has passed through the color filter are provided.

  According to the first aspect of the present invention, the incident time to each color segment is obtained from the input timing of the timing signal based on the input time interval of the timing signal output from the image display device for each period of the color segment. In addition, since it is synchronized with the timing signal input for each cycle of the color segment, the number of times of synchronization is reduced compared with the case of synchronizing for each color segment. The processing load can be reduced, and the color segment synchronized with the timing signal and the direction in which the signal level of the timing signal changes (H → L or L → H) can be arbitrarily selected, so that the timing shift can be reduced. By selecting the appropriate conditions, the timing for switching the color segment and the timing for changing the lamp power or lamp current Between displacement and small, it will exhibit the effect that color representation performance can be improved.

  According to the invention of claim 2, when the rotation speed of the color filter changes, the incident time to each color segment in the next period is detected from the time interval for one period after the rotation speed changes. Therefore, even if the incident time to each color segment changes due to a change in the rotation speed, it is possible to follow the change in the incident time of each color segment from the next period, and to realize a desired color. it can.

  According to the invention of claim 3, since the incident time to each color segment in the next cycle is detected from the time interval of a plurality of cycles, for example, the average value of the time intervals of a plurality of cycles is applied to each color segment. By detecting the incident time, it is possible to obtain the incident time to each color segment with high accuracy even when the timing signal itself has a time variation, thereby realizing a desired color.

  According to the fourth aspect of the present invention, the time width of the timing signal is equal to the time when the lamp light beam is incident on the color segment at the beginning of one cycle. Therefore, the change in the rotational speed can be detected from the change in the time width. . When the rotation speed changes, the incident time of each color segment is calculated based on the time width of the color segment at the beginning of one cycle and the ratio of the rotation angle of each color segment. Since the incident time of each color segment is changed within the period in which the color is detected and power corresponding to each segment can be supplied to the high pressure discharge lamp, a desired color can be realized.

  According to the fifth aspect of the present invention, it is possible to cope with an arbitrary rotation speed of the force Luller filter, and even when the rotation speed increases during one rotation of the color filter, it is possible to reduce the variation in time shift. Can be realized.

  According to the sixth aspect of the present invention, the white color segment is provided to improve the brightness, and in order to realize a desired color even if a time shift occurs at the timing of switching to the white color segment. Since there is no influence, a desired color can be realized by absorbing the variation in time deviation at the timing of switching to the white color segment.

  According to the seventh aspect of the present invention, an image with high color accuracy can be obtained by using a discharge lamp lighting device that has a small timing shift even though the number of times that the color segment switching timing and the output switching timing are synchronized is small. A display device can be provided.

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

(Embodiment 1)
The discharge lamp lighting device of the present invention is used for an image display device, and the image display device is a discharge lamp lighting device 101 for lighting a high pressure discharge lamp La as a light source as described in FIG. A rotary color filter 103 that is divided into a plurality of color segments 103a in the rotation direction and is irradiated with light beams emitted from the high-pressure discharge lamp sequentially into the color segments 103a according to the rotation, and the high-pressure discharge lamp A lens 104 that condenses the light emitted from La on the color filter 103, a lens 105 that condenses the light that has passed through the color filter 103 onto an optical element 106, which will be described later, and a luminous flux of each color that has entered through the lens 105. A reflective optical element 106 (image display element) called DMD (registered trademark) that performs gradation and modulation by a video signal, and optical element 1 The projection lens 107 for projecting the light reflected by the projection surface 6 and the rotation of the color filter 103 and the image display for controlling the light output of the high-pressure discharge lamp La according to the color segment 103a on which the lamp luminous flux enters. Control circuit 102.

  FIG. 1 is a circuit block diagram of the discharge lamp lighting device 101. The lighting circuit including the converter circuit 1 and the inverter circuit 2, the load circuit 3, the lamp voltage detection circuit 4, and the control circuit 5 are the main components. Prepare.

  The converter circuit 1 is formed of a conventionally known step-down chopper circuit using a switching element Q1 made of a MOSFET, an inductor L1, a capacitor C1, and a diode D1, and switches the DC voltage of the DC power source E by the switching element Q1. As a result, a voltage obtained by stepping down the power supply voltage is generated.

  The inverter circuit 2 includes a full bridge circuit 2a using the switching elements Q2 to Q5, a drive circuit 2b that individually turns on / off the switching elements Q2 and Q3 according to a control signal input from the control circuit 5, and a control circuit Drive circuit 2c for individually turning on / off switching elements Q4 and Q5 in response to a control signal input from 5, and between a connection point of switching elements Q2 and Q3 and a connection point of switching elements Q4 and Q5. A load circuit 3 is connected. Here, the drive circuits 2b and 2c alternately turn on / off the group of switching elements Q2 and Q5 and the group of switching elements Q3 and Q4 in accordance with the control signal, and the output voltage of the converter circuit 1 Is applied to the load circuit 3.

  The load circuit 3 is connected in parallel with an LC resonance circuit including an inductor L2 and a capacitor C2 connected in series between a connection point of the switching elements Q2 and Q3 and a connection point of the switching elements Q4 and Q5, and the capacitor C2. And a high-pressure discharge lamp La.

  The lamp voltage detection circuit 4 is composed of a voltage dividing circuit of resistors R2 and R3 that divides the output voltage of the converter circuit 1, and the voltage at the connection point of the resistors R2 and R3 is taken into the control circuit 5.

  The control circuit 5 includes a microcomputer 6, a D / A converter 5 a configured by, for example, an R-2R circuit and D / A converting a control signal input from the microcomputer 6, an output of the D / A converter 5 a, and a lamp current. A PWM control circuit 5b that performs PWM control of the switching element Q1 based on the detection result; a full bridge control unit 5c that outputs control signals for the switching elements Q2 to Q5 to the drive circuits 2b and 2c based on a control signal from the microcomputer 6; The timing at which the timing signal output from the image display device side (image display control circuit 102) is received and output to the microcomputer 6 every time the color filter rotates once (that is, every time the plurality of color segments 103a make a round). And a signal input circuit 5d.

  The microcomputer 6 also has an A / D converter 6a to which the voltage Vla detected by the lamp voltage detection circuit 4 is input, and a power for outputting a control signal for controlling the output power of the converter circuit 1 to the D / A converter 5a. Control reference signal generation processing unit 6b, power control amount control data corresponding to the lamp voltage, data necessary for calculating the time of each color segment (for example, the rotation angle of each color segment), and a full bridge circuit Based on the data table 6c storing timing data for inverting the output of 2a and the time interval of the timing signal input via the timing signal input circuit 5d, the luminous flux is applied to each color segment from the time of receiving the timing signal. A segment time calculation processing unit 6d (segment incident time detecting means) for determining an incident time until the incident And a time setting section 6e which the light flux in each segment based on the incident time of each segment detected by the segment time calculation processing unit 6d starting from the input time point of the signal to set the time the incident.

  Here, FIG. 2A shows a change pattern of the color segment 103a on which the lamp light beam is incident, and FIG. 2B shows a synchronization output from the output circuit of the image display control circuit 102 (consisting of the transistor Tr1 and the resistor R10). FIG. 2C is a waveform diagram of the timing signal CS0, FIG. 2C is a waveform diagram of the timing signal CS1 output from the timing signal input circuit 5d, and FIG. 2D is a waveform diagram of the lamp current ILa. In the example of FIG. The filter 103 is divided into six color segments 103a of C (Cyan), B (Blue), R (Red), Y (Yellow), G (Green), and W (White) in the rotation direction. The luminous flux from the high-pressure discharge lamp La is incident on each color segment 103a in the order of C → B → R → Y → G → W → C. The synchronization timing signal CS0 is input in synchronization with the start of one cycle of the color filter 103, and the rising timing of the synchronization timing signal CS0 is the timing at which the color segment 103a switches from W to C (that is, the end of the white color segment). At the time point or the start point of the cyan color segment 103a). Since the timing signal input circuit 5d is configured using the photocoupler PC1, the timing signal CS1 has almost no time shift at the rising edge of the timing signal CS0, but at the falling edge of the timing signal CS0, Since the signal waveform of the timing signal CS1 is rounded, a time shift occurs until the timing signal CS1 falls below the threshold level (see FIG. 16).

  The control circuit 5 adjusts the power supplied to the high-pressure discharge lamp La by controlling the output power of the converter circuit 1. The detection voltage Vla is input from the lamp voltage detection circuit 4 to the A / D conversion unit 6a of the microcomputer 6, and a value obtained by D / A converting the detection voltage Vla is output to the power control reference signal generation processing unit 6b. The lamp voltage is detected at any one of the following four detection timings. The four detection timings indicate that the input power (current) to the high-pressure discharge lamp La is 100% (rectangular wave). The timing provided in the segment to be turned on, and the incident time of the lamp light flux is relatively long (that is, the rotation angle is relatively large) (for example, the red (R) color segment in the example of FIG. 2) The timing provided in the segment, the timing provided in the segments (blue (B) and red (R) color segments in the example of FIG. 2) in which the input power (current) to the high-pressure discharge lamp La is continuous at the same value, At the timing provided in the segment (blue (B) or red (R) color segment in the example of FIG. 3) in which the input power (current) to the high pressure discharge lamp La is the same value in the image mode. That. 3A is a change pattern of the color segment 103a on which the lamp light beam is incident, FIG. 3B is a waveform diagram of the synchronization timing signal CS0, FIG. 3C is a waveform diagram of the timing signal CS1, and FIG. d) is a waveform diagram of the lamp current ILa in the case of the image mode 1, FIG. 8E is a waveform diagram of the lamp current ILa in the case of the image mode 2, and FIG. It is a chart which shows the setting of the lamp electric power in a color segment.

  The power control reference signal generation processing unit 6b refers to the data table 6c based on the A / D converted detection voltage Vla, obtains a lamp power control amount necessary for the corresponding color segment, and performs D / A conversion. The signal is output to the unit 5a, and converted to the DC voltage Ip by the D / A conversion unit 5a.

  The PWM control circuit 5b includes the output voltage Ip of the D / A converter 5a and the voltage across the resistor R1 connected between the negative electrode of the DC power supply E and the diode D1 (corresponding to the actual value of the lamp current). The chopper control is performed based on the input voltage across the resistor R1 fed back and the command voltage, and the lighting power supplied to the high pressure discharge lamp La is controlled.

  In the microcomputer 6, the polarity of the output of the full bridge circuit 2a is inverted by the control signal output to the full bridge control unit 5c, and the timing at which the signal level of the timing signal CS1 input from the timing signal input circuit 5d changes. The polarity of the output of the full bridge circuit 2a is inverted in accordance with the timing when the color segment 13a of the color filter 13 is switched. When the light source is a direct-current lamp, it is not necessary to reverse the polarity of the output of the full bridge circuit 2a.

  By the way, when the high pressure discharge lamp La is started, the control circuit 5 causes the full bridge circuit 2a to operate at a high frequency, thereby causing resonance in the resonance circuit composed of the inductor L2 and the capacitor C2, and increasing the resonance voltage generated in the resonance circuit to high pressure. It is applied to the discharge lamp La to cause dielectric breakdown, and the high pressure discharge lamp La is turned on. Thereafter, in order to shift to arc discharge, the control circuit 5 operates the full bridge circuit 2a for a while (for example, about several hundred mS to several tens of seconds) with a high frequency operation (for example, 1 kHz or more), and then a low frequency operation. (For example, 1 kHz or less), and full-bridge control corresponding to the intended use or brightness is started from the point of transition to low-frequency operation. In the circuit of FIG. 1, the high pressure discharge lamp La is dielectrically broken by the resonance operation of the resonance circuit. However, the high pressure discharge lamp La may be broken down using an igniter, or a full bridge circuit. The igniter may be activated while the 2a is operating at a high frequency. In addition, the control circuit 5 operates the low frequency of the full bridge circuit 2a from the beginning, causes the dielectric breakdown by the igniter to turn on the high pressure discharge lamp La, and then controls the lamp current according to the usage or brightness. Alternatively, lamp power control may be started.

  Here, the control flow of the present embodiment will be described with reference to the flowchart of FIG. First, the segment time calculation processing unit 6d of the microcomputer 6 detects the falling edge of the timing signal CS1 (S1 in FIG. 6). Here, since the timing signal CS1 is output in synchronization with the color segment (C) at the beginning of one cycle, the timing when the color segment is switched from W to C by detecting the falling edge of the timing signal CS1. That is, the start point of one cycle can be detected. As shown in FIG. 16, the falling edge (H → L) of the timing signal CS1 when the photocoupler PC1 of the timing signal input circuit 5d is turned on has a smaller round of signal waveform than the rising edge when turned off. The segment time calculation processing unit 6d detects the color segment switching timing by detecting the falling edge of the timing signal CS1.

  Next, in the case where the light source is an AC lamp and the setting is made so that the polarity of the full bridge circuit 2a is reversed when the falling edge of the timing signal is detected, the time setting processing unit 6e of the microcomputer 6 controls the full bridge control unit 5c. Then, a signal obtained by inverting the polarity of the control signals FB1 and FB2 is output to invert the polarity of the lamp current (S2). Thereafter, the power control reference signal generation processing unit 6b of the microcomputer 6 refers to the data table 6c to control the power for the initial segment (color segment synchronized with the fall of the timing signal CS1, which is cyan in the case of FIG. 2). The amount is set (S3), D / A conversion is performed by the D / A converter 5a, and the lamp power is controlled to a predetermined value by the PWM control circuit 5b. Next, the segment time calculation processing unit 6d of the microcomputer 6 calculates a time interval T1 from the previous detection of the timing signal CS1 to the current detection (S4). When the timing signal CS1 is detected and the time interval is measured, when the R8C / Tiny series R8C / 26 group manufactured by Renesas Technology Corporation is used as the microcomputer 6, the timing is measured using the pulse period measurement mode of the timer function. The level change (H → L) of the signal CS1 may be detected and the time may be measured.

When the time interval T1 of the timing signal CS1 is obtained, the segment time calculation processing unit 6d of the microcomputer 6 calculates the time for the lamp light beam to enter each color segment by the following method for each color segment (S5 to S10). . As shown in FIG. 2, when the signal level change (H → L) of the timing signal CS1 is one time while the color filter 103 rotates once, the time interval T1 of the timing signal CS1 is 1 for the power Luller filter 103. It is equal to the rotation period and corresponds to an angle of one rotation (= 360 degrees). Here, since the angle of each color segment 103a of the force Luller filter 103 is determined in advance, if the angle of each color segment 103a is stored in the data table 6c, the segment time calculation processing unit 6d reads from the data table 6c. The time Tx (= t1 _C , t1 _B , t1 _R , t1 _Y , t1 _G , t1 _{W) at} which the lamp luminous flux is incident on each color segment 103 a using the read angle θx of each color segment 103 a and the time interval T1 described above. ) Can be calculated by the following equation (1).

Tx = (θx / 360) × T1 (1)
Then, by accumulating the time Tx during which the lamp luminous flux is incident on each color segment 103a, it is possible to obtain the incident time from when the timing signal is received until the luminous flux is incident on each color segment 103a. When the incident time of each color segment 103a is obtained, the microcomputer 6 detects the fall of the timing signal CS1 (S11). This is because when the rotation speed of the color filter 103 is increased as shown in FIG. 4, the incident time of each color segment 103a is calculated from the period T1 at the rotation speed of the color filter 103 before one rotation. When the falling edge of the timing signal CS1 is detected after the acceleration, the cycle is T2 (<T1), and the time and power of each color segment set based on the previous cycle T1 is the actual color segment. Will not match. Therefore, the process of detecting the falling edge of the timing signal CS1 is performed during the control (S11), and when the falling edge is detected, it is determined that the rotation speed has increased, and the process returns to step S2 to shift to the initial segment process. It has become.

  Next, the time setting processing unit 6e of the microcomputer 6 determines whether or not the time (the time Tx obtained in S5 to S10) from the switching to the current color segment 103a to the switching to the next color segment 103a has elapsed (that is, the timing). It is determined whether or not the incident time of each color segment has elapsed since the signal was received (S12). If the incident time has not elapsed, the process returns to S11. If the incident time has elapsed, the power is returned. The control reference signal generation processing unit 6b refers to the data table 6c, sets the power control amount corresponding to the next color segment 103a (S13), is D / A converted by the D / A conversion unit 5a, and is subjected to PWM control. The circuit 5b controls the lamp power according to the color segment 103a and sets the time condition for the next color segment 103a. Is carried out (S14). Further, as shown in FIG. 5, when the polarity of the lamp current needs to be changed during one cycle of the color filter 103 (color segment 103a), the time setting processing unit 6e of the microcomputer 6 changes to the full bridge control unit 5c. On the other hand, a signal obtained by inverting the polarities of the control signals FB1 and FB2 is output, and the polarity of the lamp current is inverted (S15). Thereafter, the microcomputer 6 determines whether or not the current color segment 103a is the color segment 103a at the end of one cycle (white in the example of FIG. 2) (S16). If it is not the final color segment 103a, the process returns to S11. Waiting for the incident time of the current color segment 103a to elapse. In the case of the last color segment 103a, the power control amount in the last segment is maintained until the next falling edge of the timing signal CS1 is detected. When the rotation speed of the color filter 103 is reduced, that is, when the detection interval T1 of the falling edge of the timing signal CS1 becomes longer, the color filter 103 is absorbed by extending the time of the last color segment 103a, and each time from the next cycle. The incident time of the color segment 103a is changed. The white (W) color segment 103a is provided to improve the brightness, and the timing at which the timing signal CS1 is input is the end point of the white color segment 103a. Accordingly, even if a time shift occurs at the timing of switching to the white color segment 103a, there is no effect to achieve the desired color, so by absorbing the time shift variation at the timing of switching to the white color segment, A desired color can be realized.

  And if the segment time calculation process part 6d of the microcomputer 6 detects the fall of the timing signal CS1 again, the microcomputer 6 will start control operation from the process of S1 mentioned above.

  As described above, in the present embodiment, by performing the control according to the flowchart of FIG. 6, each color segment 103 a of the color filter 103 is transmitted from the control circuit 102 for image display to the discharge lamp lighting device 101 with a simple signal. The time lag between the timing of switching and the timing of changing the lamp power (lamp current) supplied to each color segment 103a can be reduced, and even if the rotational speed of the color filter 103 changes, it immediately follows (from the next cycle). Therefore, a desired color can be realized.

(Embodiment 2)
A second embodiment of the present invention will be described with reference to FIGS. Note that the configurations of the discharge lamp lighting device and the image display device are the same as those of the first embodiment, and therefore, common components are denoted by the same reference numerals and description thereof is omitted.

In the first embodiment, the microcomputer 6 calculates the incident time of each color segment in the next one cycle of the color filter 103 from the time interval T1 of one cycle of the timing signal CS1, but in this embodiment, the timing is From the time interval (T1 + T2) of two periods of the signal CS1, the incident times t1 _C , t1 _B , t1 _R , t1 _Y , t1 _G , t1 _W of each color segment in the next one period of the color filter 103 are calculated. From the time interval (T2 + T3) of the next two periods of the timing signal CS1, the incident time T2 _C , T2 _B , T2 _R , T2 _Y , T2 _G , T2 of each color segment in the next one period of the color filter 103. _W is calculated. FIG. 7 is a waveform diagram of each part, FIG. 7 (a) is a change pattern of the color segment 103a on which the lamp light beam is incident, and FIG. 7 (b) is a waveform diagram of the timing signal CS1 output from the timing signal input circuit 5d. FIG. 7C is a waveform diagram of the lamp current ILa. In the example of FIG. 7, the color filter 103 is rotated in the rotation direction by C (Cyan), B (Blue), R (Red), Y (Yellow), G (Green). ), W (White), which are divided into six color segments 103a, and according to the rotation, the light flux from the high pressure discharge lamp La is in the order of C → B → R → Y → G → W → C. It is made to enter. The synchronization timing signal CS0 is input in synchronization with the start of one cycle of the color filter 103 (color segment 103a), and the rising timing of the synchronization timing signal CS0 is synchronized with the timing at which the color segment 103a is switched from W to C. ing.

  Here, the control flow of the present embodiment will be described with reference to the flowchart of FIG. First, the segment time calculation processing unit 6d of the microcomputer 6 detects the falling edge of the timing signal CS1, thereby detecting the start point of one cycle of the color segment 103a (S1 in FIG. 8). Next, in the case where the light source is an AC lamp and the setting is made so that the polarity of the full bridge circuit 2a is reversed when the falling edge of the timing signal is detected, the time setting processing unit 6e of the microcomputer 6 controls the full bridge control unit 5c. Then, a signal obtained by inverting the polarity of the control signals FB1 and FB2 is output to invert the polarity of the lamp current (S2). Thereafter, the power control reference signal generation processing unit 6b of the microcomputer 6 refers to the data table 6c, and the power control amount for the initial segment (the color segment synchronized with the fall of the timing signal CS1 and cyan in the present embodiment). (S3), D / A conversion is performed by the D / A converter 5a, and the lamp power is controlled to a predetermined value by the PWM control circuit 5b. Next, the segment time calculation processing unit 6d of the microcomputer 6 calculates the time interval Tnew from the time when the timing signal CS1 was detected to the time of the current detection (S4), and the time from the time when the timing signal CS1 was detected before the previous time. The time interval until detection is stored in the data table 6c as Tod (S5). When the timing signal CS1 is detected and the time interval is measured, when the R8C / Tiny series R8C / 26 group manufactured by Renesas Technology Corporation is used as the microcomputer 6, the timing is measured using the pulse period measurement mode of the timer function. The level change (H → L) of the signal CS1 may be detected and the time may be measured.

When the time intervals Tnew and Told of the timing signal CS1, that is, the current cycle Tnew and the previous cycle Told of the color filter 103 are obtained, the segment time calculation processing unit 6d of the microcomputer 6 averages the current cycle Tnew and the previous cycle Told. After obtaining the value avr (T) = (Tnew + Told) / 2 (S6), for each color segment, the time during which the lamp light flux enters each color segment is calculated by the following method (S7 to S12). As shown in FIG. 7, when the signal level change (H → L) of the timing signal CS1 is one time while the color filter 103 rotates once, the time interval T of the timing signal CS1 is 1 for the force Luller filter 103. It is equal to the rotation period and corresponds to an angle of one rotation (= 360 degrees). Here, since the angle of each color segment 103a of the force Luller filter 103 is determined in advance, if the angle of each color segment 103a is stored in the data table 6c, the segment time calculation processing unit 6d reads from the data table 6c. The time Tx (= t1 _C , t1 _B , t1 _R , t1 _Y ) at which the lamp luminous flux is incident on each color segment 103a using the read angle θx of each color segment 103a and the average value avr (T) of the above time interval. , T1 _G , t1 _W ) can be calculated by the following equation (2).

Tx = (θx / 360) × avr (T) (2)
Then, by accumulating the time Tx during which the lamp luminous flux is incident on each color segment 103a, it is possible to obtain the incident time from when the timing signal is received until the luminous flux is incident on each color segment 103a. When the incident time of each color segment 103a is obtained, the microcomputer 6 detects the fall of the timing signal CS1 (S13). This is because, when the rotation speed of the color filter 103 is increased, the incident time of each color segment 103a is calculated from the period T1 at the rotation speed of the color filter 103 before one rotation. The period is T2 (<T1) at the time when the falling edge is detected, and the time and power of each color segment set based on the previous period T1 do not match the actual color segment. Therefore, the process of detecting the falling edge of the timing signal CS1 is performed during the control (S13). When the falling edge is detected, it is determined that the rotational speed has increased, and the process returns to step S2 to shift to the initial segment process. It has become.

  Next, the time setting processing unit 6e of the microcomputer 6 determines whether or not the time from when the current color segment 103a is switched to when the next color segment 103a is switched (time Tx obtained in S7 to S12) has elapsed (that is, the timing). It is determined whether or not the incident time of each color segment has elapsed since the signal was received (S14). If the incident time has not elapsed, the process returns to S13. If the incident time has elapsed, the power control is performed. The reference signal generation processing unit 6b refers to the data table 6c, sets the power control amount for the next color segment 103a (S15), is D / A converted by the D / A conversion unit 5a, and is ramped by the PWM control circuit 5b. The power is controlled to a value corresponding to the color segment, and the time condition is set for the next color segment 103a (S 6). When it is necessary to change the polarity of the lamp current in the middle of one cycle of the color filter 103, the polarity of the control signals FB1 and FB2 is reversed from the time setting processing unit 6e of the microcomputer 6 to the full bridge control unit 5c. The signal is output and the polarity of the lamp current is inverted (S17). Thereafter, the microcomputer 6 determines whether or not the current color segment 103a is the color segment 103a (white in this embodiment) at the end of one cycle (S18). If it is not the final color segment 103a, the process returns to S11, In the case of the last color segment 103a, the power control amount in the last segment is maintained until the next falling edge of the timing signal CS1 is detected. When the rotation speed of the color filter 103 is reduced, that is, when the detection interval T1 of the falling edge of the timing signal CS1 becomes longer, the color filter 103 is absorbed by extending the time of the last color segment 103a, and each period from the next cycle. The incident time of the color segment 103a is changed. And if the segment time calculation process part 6d of the microcomputer 6 detects the fall of the timing signal CS1 again, the microcomputer 6 will start control operation from the process of S1 mentioned above.

In the control flow described above, the microcomputer 6 performs the incident time t1 _C , t1 _B , t1 _R , and the incident time of each color segment in the next one cycle of the color filter 103 from the time interval (T1 + T2) corresponding to two cycles of the timing signal CS1. Although t1 _Y , t1 _G , and t1 _W have been calculated, the incident time t1 _C and t1 _B of each color segment in the next two periods of the color filter 103 from the time interval (T1 + T2) of two periods of the timing signal CS1. , T1 _R , t1 _Y , t1 _G , t1 _W, and from the time interval (T3 + T4) for the next two periods of the timing signal CS1, the incident time of each color segment in the next two periods of the color filter 103 _{T2 C, T2 B, T2 R} , T2 Y, T2 G, T2 W may be calculated. FIG. 9 is a waveform diagram of each part, FIG. 9A is a change pattern of the color segment 103a on which the lamp light beam is incident, and FIG. 9B is a waveform diagram of the timing signal CS1 output from the timing signal input circuit 5d. FIG. 4C is a waveform diagram of the lamp current ILa.

  Here, the control flow in this case will be described with reference to the flowchart of FIG. First, the segment time calculation processing unit 6d of the microcomputer 6 detects the falling edge of the timing signal CS1, thereby detecting the start time of one cycle (S1 in FIG. 10), and the number of detections of the timing signal CS1 is 1. Is counted up (S2).

  Next, when the light source is an AC lamp and the setting is made so that the polarity of the full bridge circuit 2a is reversed when the falling edge of the timing signal is detected, the time setting processing unit 6e of the microcomputer 6 controls the full bridge control unit 5c. A signal obtained by inverting the polarities of the control signals FB1 and FB2 is output to invert the polarity of the lamp current (S3).

  Thereafter, the power control reference signal generation processing unit 6b of the microcomputer 6 refers to the data table 6c, and the power control amount for the initial segment (the color segment synchronized with the fall of the timing signal CS1 and cyan in the present embodiment). (S4), D / A conversion is performed by the D / A converter 5a, and the lamp power is controlled to a predetermined value by the PWM control circuit 5b.

  Next, the segment time calculation processing unit 6d of the microcomputer 6 calculates the time interval Tnew from the time when the timing signal CS1 was detected to the time of the current detection (S5), and the time from the time when the timing signal CS1 was detected before the previous time. The time interval until detection is stored in the data table 6c as Tod (S6). When the timing signal CS1 is detected and the time interval is measured, when the R8C / Tiny series R8C / 26 group manufactured by Renesas Technology Corporation is used as the microcomputer 6, the timing is measured using the pulse period measurement mode of the timer function. The level change (H → L) of the signal CS1 may be detected and the time may be measured.

When the time intervals Tnew and Told of the timing signal CS1, that is, the current cycle Tnew and the previous cycle Told of the color filter 103 are obtained, the segment time calculation processing unit 6d of the microcomputer 6 determines whether or not the timing signal detection count is the second time. Is determined (S7). When the number of times of detection is the second time, the process proceeds to S8 and S9 in order to perform a process of updating the average value of the two cycles. That is, after resetting the number of detections to 0 (S8), an average value avr (T) = (Tnew + Told) / 2 of the current cycle Tnew and the previous cycle Told is obtained (S9), and each color segment is assigned to each color segment. A time Tx during which the lamp light beam enters is calculated (S10 to S15). On the other hand, when the number of detections is the first time in S7, the process of updating the average value of the period is not performed, and therefore the segment time calculation processing unit 6d of the microcomputer 6 proceeds to the processing of S10 to S15, and each color The time for the lamp light beam to enter each color segment is calculated for the segment. Here, the calculation method of the time for which the lamp luminous flux enters each color segment is as follows. As shown in FIG. 9, when the signal level change (H → L) of the timing signal CS1 is one time during one rotation of the color filter 103, the time interval T of the timing signal CS1 is 1 for the force Lur filter 103. It is equal to the rotation period and corresponds to an angle of one rotation (= 360 degrees). Here, since the angle of each color segment 103a of the force Luller filter 103 is determined in advance, if the angle of each color segment 103a is stored in the data table 6c, the segment time calculation processing unit 6d reads from the data table 6c. The time Tx (= t1 _C , t1 _B , t1 _R , t1 _Y ) at which the lamp luminous flux is incident on each color segment 103a using the read angle θx of each color segment 103a and the average value avr (T) of the above time interval. , T1 _G , t1 _W ) can be calculated by the above equation (2).

  Then, by accumulating the time Tx during which the lamp luminous flux is incident on each color segment 103a, it is possible to obtain the incident time from when the timing signal is received until the luminous flux is incident on each color segment 103a. When the incident time of each color segment 103a is obtained, the microcomputer 6 detects the fall of the timing signal CS1 (S16). This is because when the rotation speed of the color filter 103 increases, the incident time of each color segment 103a is calculated from the period T1 at the rotation speed of the color filter 103 before one rotation, and therefore the falling edge of the timing signal CS1. The period of time is detected as T2 (<T1), and the time and power of each color segment set based on the previous period T1 do not match the actual color segment. Therefore, the process of detecting the falling edge of the timing signal CS1 is performed during the control (S16), and when the falling edge is detected, it is determined that the rotation speed has increased, and the process returns to step S2 to shift to the initial segment process. It has become.

  Next, the time setting processing unit 6e of the microcomputer 6 determines whether or not the time (the time Tx obtained in S10 to S15) from the switching to the current color segment 103a to the switching to the next color segment 103a has elapsed (that is, the timing). It is determined whether or not the incident time of each color segment has elapsed since the signal was received (S17). If the incident time has not elapsed, the process returns to S16. If the incident time has elapsed, the power control is performed. The reference signal generation processing unit 6b refers to the data table 6c, sets the power control amount for the next color segment 103a (S18), is D / A converted by the D / A conversion unit 5a, and is ramped by the PWM control circuit 5b. The power is controlled to a value corresponding to the color segment, and the time condition is set for the next color segment 103a ( 19). When it is necessary to change the polarity of the lamp current during one cycle of the color filter 103, the polarity of the control signals FB1 and FB2 is inverted from the time setting processing unit 6e of the microcomputer 6 to the full bridge control unit 5c. The signal is output and the polarity of the lamp current is inverted (S20). Thereafter, the microcomputer 6 determines whether or not the current color segment 103a is the color segment 103a (white in this embodiment) at the end of one cycle (S21). If it is not the final color segment 103a, the process returns to S11, Wait until the incident time of the color segment 103a elapses. In the case of the final color segment 103a, the power control amount in the final segment is maintained until the next falling edge of the timing signal CS1 is detected. When the rotation speed of the color filter 103 is reduced, that is, when the detection interval T1 of the falling edge of the timing signal CS1 becomes longer, the color filter 103 is absorbed by extending the time of the last color segment 103a, and each time from the next cycle. The incident time of the color segment 103a is changed. And if the segment time calculation process part 6d of the microcomputer 6 detects the fall of the timing signal CS1, the microcomputer 6 will start control operation from the process of S1 mentioned above.

  In this embodiment, when the level change of the timing signal CS1 is detected twice, the incident time of each color segment 103a in the next one or two cycles is obtained, but the level change of the timing signal CS1 is detected three times. When the above predetermined number of times is detected, the incident time of each color segment 103a in the next one or a plurality of cycles may be obtained.

  Further, as described above, in the present embodiment, by performing control according to the flowchart of FIG. 8 or FIG. 10, each color of the color filter 103 is transmitted from the control circuit 102 for image display to the discharge lamp lighting device 101 with a simple signal. The time difference between the timing at which the segment 103a is switched and the timing at which the lamp power (lamp current) supplied to each color segment 103a is changed can be reduced, and when the time interval itself of the timing signal CS1 varies, a plurality of times are generated. By taking the average value of the time intervals, it is possible to obtain a value close to the original time interval, and by calculating the incident time of each color segment 103a using this average value, the switching of each color segment 103a is performed. The time difference between the timing and the lamp power or lamp switching timing Can be reduced, it is possible to realize a desired color.

(Embodiment 3)
A third embodiment of the present invention will be described with reference to FIGS. Note that the configurations of the discharge lamp lighting device and the image display device are the same as those of the first embodiment, and therefore, common components are denoted by the same reference numerals and description thereof is omitted.

  FIG. 11 is a waveform diagram of each part of the discharge lamp lighting device, FIG. 11 (a) is a change pattern of the color segment 103a on which the lamp luminous flux is incident, and FIG. 11 (b) is a timing signal output from the timing signal input circuit 5d. The waveform diagram of CS1 is a waveform diagram of the lamp current ILa. In the example of FIG. 11, the color filter 103 is C (Cyan), B (Blue), R (Red), Y (Yellow) in the rotation direction. ), G (Green), W (White) are divided into six color segments 103a, and the light flux from the high-pressure discharge lamp La is in the order of C → B → R → Y → G → W → C. So that it is incident on each color segment 103a. The synchronization timing signal CS0 is input while the light beam is incident on the color segment 103a at the beginning of one cycle, and the time width of the synchronization timing signal CS1 is substantially equal to the time when the lamp light beam is incident on the cyan color segment 103a. It has become. The falling timing of the synchronization timing signal CS1 is synchronized with the timing at which the color segment 103a is switched from W to C.

  In the first and second embodiments described above, the incident time of each color segment 103a is obtained using the time interval of the timing signal CS1 and the angle data of each color segment 103a, but the rotational speed of the color filter 103 changes midway. In this case, the incident time of each color segment 103a is different from the actual time in the first period when the rotation speed is changed. Therefore, in this embodiment, when the rotation speed of the color filter 103 changes, the incident time of the initial segment is obtained based on the time width of the timing signal CS1, and the incident time of the initial segment and the rotation angle of each color segment 103a are obtained. The incident time of each color segment 103a is calculated on the basis of the ratio.

  Here, the control flow of the present embodiment will be described with reference to the flowchart of FIG. First, the segment time calculation processing unit 6d of the microcomputer 6 detects the falling edge of the timing signal CS1, thereby detecting the start point of one cycle of the color segment 103a (S1 in FIG. 12). Next, in the case where the light source is an AC lamp and the setting is made so that the polarity of the full bridge circuit 2a is reversed when the falling edge of the timing signal is detected, the time setting processing unit 6e of the microcomputer 6 controls the full bridge control unit 5c. Then, a signal obtained by inverting the polarity of the control signals FB1 and FB2 is output to invert the polarity of the lamp current (S2). After that, the power control reference signal generation processing unit 6b of the microcomputer 6 refers to the data table 6c and controls the power for the initial segment (color segment synchronized with the fall of the timing signal CS1, which is cyan in the case of FIG. 11). The amount is set (S3), D / A conversion is performed by the D / A converter 5a, and the lamp power is controlled to a predetermined value by the PWM control circuit 5b. Next, the segment time calculation processing unit 6d of the microcomputer 6 calculates a time interval T1 from the previous detection of the timing signal CS1 to the current detection (S4). When the timing signal CS1 is detected and the time interval is measured, when the R8C / Tiny series R8C / 26 group manufactured by Renesas Technology Corporation is used as the microcomputer 6, the timing is measured using the pulse period measurement mode of the timer function. The level change (H → L) of the signal CS1 may be detected and the time may be measured.

  Next, when the segment time calculation processing unit 6d of the microcomputer 6 detects the rising edge of the timing signal CS1 and the signal level of the timing signal CS1 is switched from H to L, the signal level is switched from L to H. Until the time (that is, the time width T1 ′ of the timing signal CS1) is detected by a timer mounted on the microcomputer 6 (S5), for example, from the change of the time width T1 ′ of the timing signal CS1, the rotational speed of the color filter 103 is changed. It is determined whether or not it has changed (S6). Here, when the rotation speed does not change, the segment time calculation processing unit 6d of the microcomputer 6 calculates the incident time of each color segment 103a using the time interval T1 of the timing signal CS1 and the angle data of each color segment 103a. Processing to calculate is performed (S7 to S12). On the other hand, when the rotation speed of the color segment 103a changes, the segment time calculation processing unit 6d of the microcomputer 6 compares the time width T1 ′ of the timing signal CS1 (that is, the time width of the initial segment) and the ratio of the rotation angle of each color segment 103a. Are used to calculate the incident time of each color segment (S7 ′ to S12 ′).

A method for calculating the incident time of each color segment when there is no change in the rotation speed of the color filter 103 is as follows. As shown in FIG. 11, when the signal level change (H → L) of the timing signal CS1 is one time during one rotation of the color filter 103, the time interval T1 of the timing signal CS1 is 1 for the power Luller filter 103. It is equal to the rotation period and corresponds to an angle of one rotation (= 360 degrees). Here, since the angle of each color segment 103a of the force Luller filter 103 is determined in advance, if the angle of each color segment 103a is stored in the data table 6c, the segment time calculation processing unit 6d reads from the data table 6c. The time Tx (= t1 _C , t1 _B , t1 _R , t1 _Y , t1 _G , t1 _W) when the lamp luminous flux is incident on each color segment 103 a using the read angle θx of each color segment 103 a and the time interval T1 described above. ) Can be calculated by the above equation (1).

A method for calculating the incident time of each color segment when the rotation speed of the color filter 103 is changed is as follows. As shown in FIG. 11, the time width of the timing signal CS1 is substantially equal to the time when the lamp light beam is incident on the initial color segment 103a. Since the angle of each color segment 103a is determined in advance, if the angle of each color segment 103a is stored in the data table 6c, the segment time calculation processing unit 6d reads the initial color segment read from the data table 6c. Using the angle θ0, the angle θx of the other color segment 103a, and the time width T1 ′ of the timing signal CS1, the time Tx (= t1 _B , t1 _R , t1 _Y , t1 _G , t1 _W ) can be calculated by the following equation (3).

Tx = (θx / θ0) × T1 ′ (3)
Then, by accumulating the time Tx during which the lamp luminous flux is incident on each color segment 103a, it is possible to obtain the incident time from when the timing signal is received until the luminous flux is incident on each color segment 103a. When the incident time of each color segment 103a is obtained, the time setting processing unit 6e of the microcomputer 6 determines the time from switching to the current color segment 103a to switching to the next color segment 103a (S7 to S12 or S7 'to S12'). It is determined whether or not the time Tx determined in step Sx) has elapsed (that is, whether or not the incident time of each color segment has elapsed since the timing signal was received) (S13). When the incident time has elapsed, the power control reference signal generation processing unit 6b refers to the data table 6c to set the power control amount for the next color segment 103a (S14), and performs D / A conversion. When the D / A conversion is performed by the unit 5a and the lamp power is controlled to a value corresponding to the color segment by the PWM control circuit 5b. To, to set the time conditions in the next color segment 103a (S15). When the polarity of the lamp current needs to be changed in the middle of one cycle of the color filter 103, the polarity of the control signals FB1 and FB2 is inverted from the time setting processing unit 6e of the microcomputer 6 to the full bridge control unit 5c. The signal is output and the polarity of the lamp current is inverted (S16). Thereafter, the microcomputer 6 determines whether or not the current color segment 103a is the color segment 103a at the end of one cycle (white in the example of FIG. 11) (S17). If it is not the final color segment 103a, the process returns to S13. Waiting for the incident time of the current color segment 103a to elapse. In the case of the last color segment 103a, the power control amount in the last segment is maintained until the next falling edge of the timing signal CS1 is detected. When the rotation speed of the color filter 103 is reduced, that is, when the detection interval T1 of the falling edge of the timing signal CS1 becomes longer, the color filter 103 is absorbed by extending the time of the last color segment 103a, and each time from the next cycle. The incident time of the color segment 103a is changed. And if the segment time calculation process part 6d of the microcomputer 6 detects the fall of the timing signal CS1, the microcomputer 6 will start control operation from the process of S1 mentioned above.

  As described above, in the present embodiment, by performing the control according to the flowchart of FIG. 12, each color segment 103a of the color filter 103 is transmitted from the control circuit 102 for image display to the discharge lamp lighting device 101 with a simple signal. The time lag between the switching timing and the timing for changing the lamp power (lamp current) supplied to each color segment 103a can be reduced, and even if the rotation speed of the color filter 103 changes, the time from the cycle when the rotation speed changes can be reduced. Since the change can be followed, a desired color can be realized.

  In each of the above-described embodiments, it is preferable that the time of one cycle of the timing signal CS1 is 1 mS or more and 100 mS or less, and it is possible to cope with an arbitrary rotation speed of the color filter 103. Further, as shown in FIG. Since the timing signal CS1 is input a plurality of times in synchronization with the initial segment while the rotation of the color filter 103 is rotated once, the variation in time shift can be reduced even when the rotation speed of the color filter 103 is relatively increased. Each color can be realized.

  Further, the discharge lamp lighting device of each embodiment described above is used for an image display device such as a projector or a rear projection TV, and improves the accuracy of power control in a plurality of usages or brightness. By using an inexpensive discharge lamp lighting device, an image display device capable of obtaining a stable luminous flux can be realized. FIG. 14 shows an example of a projector using each of the above-described discharge lamp lighting devices. In this projector, the above-described discharge lamp lighting device 101, a power source 121, and an optical system 122 (lens and color) are provided inside a housing 120. Filter) and a cooling fan 123 are housed.

It is a circuit block diagram of the discharge lamp lighting device of Embodiment 1. It is a wave form diagram of each part same as the above, (a) is an explanatory view showing switching of color segments, (b) is a wave form diagram of the timing signal CS0, (c) is a wave form diagram of the timing signal CS1, and (d) is a lamp current. FIG. It is a wave form diagram of each part same as the above, (a) is an explanatory view showing switching of the color segment, (b) is a wave form diagram of the timing signal CS0, (c) is a wave form diagram of the timing signal CS1, (d) is an image mode 1 is a waveform diagram of lamp current in the case of 1, FIG. 3E is a waveform diagram of lamp current in the case of image mode 2, and FIG. 3F is a chart showing set values of lamp power of each color segment in each image mode. It is a wave form diagram which shows other operation same as the above, (a) is an explanatory view showing change of a color segment, (b) is a wave form figure of timing signal CS1, (c) is a wave form figure of lamp current. It is a wave form diagram which shows another operation same as the above, (a) is explanatory drawing which shows switching of a color segment, (b) is a wave form diagram of timing signal CS1, (c) is a wave form diagram of a lamp current. It is a flowchart explaining operation | movement same as the above. FIG. 4 is a waveform diagram of each part of the discharge lamp lighting device of Embodiment 2, where (a) is an explanatory diagram showing switching of color segments, (b) is a waveform diagram of a timing signal CS1, and (c) is a waveform diagram of a lamp current. is there. It is a flowchart explaining operation | movement same as the above. It is a wave form chart of each part at the time of performing another control flow same as the above, (a) is an explanatory view showing change of a color segment, (b) is a wave form figure of timing signal CS1, (c) is a wave form of a lamp current FIG. It is a flowchart explaining another operation | movement same as the above. It is a wave form diagram of each part of the discharge lamp lighting device of Embodiment 3, (a) is explanatory drawing which shows switching of a color segment, (b) is a wave form figure of timing signal CS1, (c) is a wave form figure of lamp current. is there. It is a flowchart explaining operation | movement same as the above. It is a wave form diagram which shows other operation same as the above, (a) is an explanatory view showing change of a color segment, (b) is a wave form figure of timing signal CS1, (c) is a wave form figure of timing signal CS1, (d) Is a waveform diagram of the lamp current. It is a schematic block diagram of the projector using the discharge lamp lighting device same as the above. It is a schematic block diagram of the image display apparatus using a discharge lamp lighting device same as the above. (A) is a waveform diagram of a timing signal input to the primary side of the photocoupler, and (b) is a waveform diagram of a timing signal output from the secondary side of the photocoupler.

Explanation of symbols

1 Converter circuit (lighting circuit)
2 Inverter circuit (lighting circuit)
5 Control circuit 5d Timing signal input circuit (timing signal input means)
6 microcomputer 6d segment time calculation processing section (segment incident time detection means)
La High pressure discharge lamp 101 Discharge lamp lighting device 102 Image display control circuit 103 Color segment 103a Color segment 106 Optical element (video display element)

Claims (7)

A color filter that is divided into color segments of a plurality of colors in the rotation direction, and a light beam emitted from the high-pressure discharge lamp is sequentially incident on each color segment according to the rotation, and a gradation is added to the light beam of each color that has passed through the color filter. A discharge lamp lighting device used in an image display device including a video display element that performs modulation by a video signal,
A lighting circuit for lighting a high-pressure discharge lamp;
A control circuit for controlling the output from the lighting circuit to the high-pressure discharge lamp for each color segment;
The control circuit includes a timing signal input means for inputting a timing signal output from the image display device for each cycle of the color segment, and a time interval at which the timing signal is input. Segment incident time detecting means for obtaining an incident time until the light beam enters each color segment, and the incident time to each color segment detected by the segment incident time detecting means has elapsed from the timing signal input time point A discharge lamp lighting device that controls an output from a lighting circuit to a high-pressure discharge lamp at a time according to a color segment.   The segment incident time detecting means detects the incident time to each color segment in the next period based on a time interval of one period in which the timing signal is input. Electric light lighting device.   The segment incident time detecting means detects the incident time to each color segment in the next period based on time intervals for a plurality of periods in which the timing signal is inputted. Electric light lighting device.   When the timing signal is input while the light beam enters the color segment at the beginning of one cycle, the control circuit determines whether the rotation speed of the color filter has changed based on the result of detecting the time width of the timing signal. When the rotation speed changes, the incident time to each color segment is calculated based on the detection result of the time width and the ratio of the rotation angle of each color segment. 4. The discharge lamp lighting device according to any one of items 1 to 3.   The discharge lamp lighting device according to any one of claims 1 to 4, wherein a time of one cycle in which the timing signal is input is 1 mS or more and 100 mS or less.   6. The discharge lamp according to claim 1, wherein the color filter has at least a white color segment, and the timing at which the timing signal is input is an end point of the white color segment. Lighting device.   The discharge lamp lighting device according to any one of claims 1 to 6 for lighting a high-pressure discharge lamp, and a color having a plurality of color segments and a light beam emitted from the high-pressure discharge lamp sequentially entering each segment. An image display device comprising: a filter; and a video display element that performs gradation and modulation by a video signal on a light beam of each color that has passed through the color filter.

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