JP7303990B2 - Projection device, projection control device and program - Google Patents

Description

The present invention relates to a projection device, a projection control device, and a program.

2. Description of the Related Art Conventionally, there has been disclosed a projection apparatus that time-divisionally drives a light source section that includes light emitting elements that emit light of each color. For example, in the projection device disclosed in Patent Document 1, a spoke period is set as a period during which each color light from the light source section is switched. In the spoke period, each color light is mixed. By setting in advance the components of the mixed color light for the spoke period, it is possible to set a color mode that increases the brightness or chromaticity of the image.

JP 2012-155268 A

However, in the mixed color light in the spoke period, the amount of light emitted from each light emitting element may change due to, for example, the driving current of the light emitting element changing depending on the color mode used. As a result, an image with gradation may have discontinuous gradation.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a projection apparatus, a projection control apparatus, and a program capable of maintaining the reproducibility of gradation.

A projection device according to the present invention includes a semiconductor light emitting element and a color wheel, a light source section for emitting light of a plurality of colors including light in a first wavelength band and light in a second wavelength band in a time division manner, and light from the light source section. A display element irradiated with light from a light source to form image light, a projection optical system for projecting the image light emitted from the display element onto a projection target, and an index relating to the brightness of the light emitted from the light source unit Based on this, the light of the first wavelength band and the light of the second wavelength band are mixed and emitted in the spoke period of the color wheel, which is the emission switching timing of the light of the first wavelength band and the light of the second wavelength band. a delay time setting unit that shifts the start timing of the color mixing period, and a light source driving unit that drives the light source unit based on the setting of the delay time setting unit , wherein the spoke period is divided into a plurality of parts, and the delay time is divided into a plurality of parts. The time setting unit is characterized in that the start timing of the color mixture period is set such that the changing portion of the index relating to the brightness of the light approaches one of the plurality of divided spoke periods.

A projection control apparatus according to the present invention includes a semiconductor light emitting element and a color wheel, and emits light emitted from a light source unit that emits light of a plurality of colors including first wavelength band light and second wavelength band light in a time division manner. Based on an index related to brightness, the light of the first wavelength band and the light of the second wavelength band during the spoke period of the color wheel, which is the emission switching timing of the light of the first wavelength band and the light of the second wavelength band. a delay time setting unit for shifting a start timing of a color mixture period in which colors are mixed and emitted; and a light source driving unit for driving the light source unit based on the setting of the delay time setting unit, wherein the spoke period is divided into a plurality of wherein the delay time setting unit sets the start timing of the color mixture period so that the changing portion of the index related to the brightness of the light approaches one of the spoke periods divided into a plurality of spoke periods. do .

A program according to the present invention is a program executed by a computer, the computer comprising a semiconductor light emitting device and a color wheel, and time-divisionally dividing light of a plurality of colors including first wavelength band light and second wavelength band light. The first wavelength in the spoke period of the color wheel, which is the emission switching timing of the first wavelength band light and the second wavelength band light, based on an index related to the brightness of the light emitted from the light source unit emitted at a delay time setting unit that shifts the start timing of a color mixing period in which the band light and the second wavelength band light are mixed and emitted; and a light source driving unit that drives the light source unit based on the setting of the delay time setting unit. , wherein the spoke period is divided into a plurality of parts, and the delay time setting unit adjusts the color mixing so that the changing part of the index related to the light brightness is shifted to one of the plurality of divided spoke periods. It is characterized by setting the start timing of the period .

According to the present invention, it is possible to provide a projection apparatus, a projection control apparatus, and a program capable of maintaining reproducibility of gradation.

3 is a functional circuit block diagram of the projection device according to the embodiment of the present invention; FIG. 3 is a functional circuit block diagram showing details of a control section and a light source control circuit of the projection device according to the embodiment of the present invention; FIG. 3 is a schematic plan view of the internal structure of the light source device in the projection device according to the embodiment of the present invention; FIG. 1A is a schematic front view of a fluorescent wheel, and FIG. 1B is a schematic front view of a color wheel in the light source device of the projection device according to the embodiment of the present invention; FIG. It is a timing chart figure of the projection device concerning the embodiment of the present invention. FIG. 4 is a diagram showing rising waveforms of a blue laser diode according to an embodiment of the present invention, where (a) shows the waveform before delay adjustment, and (b) shows the changing part of the waveform set so as to be closer to the center part of the spoke period. (c) shows the waveform after delay adjustment. FIG. 4 is a flow chart showing delay adjustment in the projection device according to the embodiment of the present invention;

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a functional block diagram of a projection device 10 (projection control device). The projection device 10 includes a control section 38, an input/output interface 22, an image conversion section 23, a display encoder 24, a display drive section 26, and the like. Image signals of various standards input from the input/output connector section 21 are converted into image signals of a predetermined format suitable for display by the image conversion section 23 via the input/output interface 22 and the system bus (SB) by the projection control device. It is converted so as to be unified and output to the display encoder 24 .

The control unit 38 controls the operation of each circuit in the projection apparatus 10, and includes a CPU as an arithmetic unit, a ROM that permanently stores operation programs such as various settings, and a RAM that is used as a work memory. It is composed of

The display encoder 24 develops and stores the input image signal in the video RAM 25 , generates a video signal from the contents stored in the video RAM 25 , and outputs the video signal to the display driving section 26 .

The display drive unit 26 drives the display element 51, which is a spatial light modulator (SOM), at an appropriate frame rate corresponding to the image signal output from the display encoder 24. FIG.

The projection device 10 includes a light source device 60 that emits blue wavelength band light, green wavelength band light (first wavelength band light), and red wavelength band light (second wavelength band light). The emitted light emitted from the light source device 60 is irradiated to the display element 51 and reflected by the display element 51 to form image light. The reflected image light is projected onto a screen or the like via a projection optical system 220, which will be described later.

The projection optical system 220 has a movable lens group. The movable lens group is driven by a lens motor 45 for zoom adjustment and focus adjustment.

The image compression/decompression unit 31 reads the image data recorded in the memory card 32 at the time of reproduction, and decompresses the individual image data constituting a series of moving images frame by frame. The image compression/decompression unit 31 also outputs the decompressed image data to the display encoder 24 via the image conversion unit 23, and enables the display of moving images, etc. based on the image data stored in the memory card 32. let the process take place.

The key/indicator section 37 is provided on the housing of the projection device 10 . An operation signal from the key/indicator section 37 is sent directly to the control section 38 . A key operation signal from the remote controller is received by the Ir receiver 35 , demodulated by the Ir processor 36 and output to the controller 38 .

An audio processing unit 47 is connected to the control unit 38 via a system bus (SB). The audio processing unit 47 includes a sound source circuit such as a PCM sound source, converts sound data into analog data in the projection mode and the reproduction mode, and drives the speaker 48 to amplify the sound.

The control section 38 controls the light source control circuit 41 . The light source control circuit 41 controls such that the light source device 60 emits light source light in a predetermined wavelength band required for image generation.

Further, the control unit 38 can cause the cooling fan drive control circuit 43 to perform temperature detection using a plurality of temperature sensors provided in the light source device 60 and the like, and can control the rotational speed of the cooling fan based on the temperature detection results. The control unit 38 causes the cooling fan drive control circuit 43 to continue rotation of the cooling fan even after the main body of the projection apparatus 10 is turned off by a timer or the like, or to turn off the power of the main body of the projection apparatus 10 depending on the result of temperature detection by the temperature sensor. Control such as turning off can also be performed.

Further, as shown in FIG. 2, the control section 38 of the projection control apparatus, which is the projection apparatus 10 in this embodiment, includes a timing setting section 53, a delay time setting section 54, and a light source driving section 55. FIG. The light source control circuit 41 also includes a detector 56 that detects information indicating the amount of light of each color emitted from the projection optical system 220 . Details of these will be described later.

Next, based on FIG. 3, the internal structure of the light source device 60 in the projection device 10 will be described. In the following description, left and right in the projection device 10 indicate the left and right direction with respect to the projection direction, and front and back indicate the screen side direction of the projection device 10 and the front and back direction with respect to the traveling direction of the light beam. .

The light source device 60 includes an excitation light irradiation device 70 that is a light source for blue wavelength band light and an excitation light source, a green light source device 80 that is a light source for green wavelength band light, and a red light source device that is a light source for red wavelength band light. 120 and a color wheel device 200 . The green light source device 80 is composed of the excitation light irradiation device 70 and the fluorescent wheel device 100 .

The light source device 60 is provided with a light guide optical system 140 that guides the light of each color wavelength band. The light guide optical system 140 guides the light emitted from the excitation light irradiation device 70 , the green light source device 80 and the red light source device 120 to the light source optical system 170 . The excitation light irradiation device 70 includes a blue laser diode 71 that is a plurality of semiconductor light emitting elements, condensing lenses 77 and 78 and a diffusion plate 79 .

A collimator lens 73 is arranged on the optical axis of each blue laser diode 71 to convert the light emitted from the blue laser diode 71 into parallel light so as to enhance the directivity of the light emitted from the blue laser diode 71 . The condenser lens 77 and the condenser lens 78 reduce the light beam emitted from the blue laser diode 71 in one direction and emit it to the diffuser plate 79 . The diffusion plate 79 diffuses and transmits the incident blue wavelength band light to the first dichroic mirror 141 arranged on the luminescent wheel 101 side.

The fluorescent wheel device 100 is arranged on the optical path of the excitation light emitted from the excitation light irradiation device 70 . The fluorescent wheel device 100 includes a fluorescent wheel 101 , a motor 110 , a condenser lens group 111 and a condenser lens 115 . The fluorescent wheel 101 is arranged perpendicular to the optical axis of the light emitted from the excitation light irradiation device 70 so that the upper position of the fluorescent wheel 101 is the irradiation position S (see FIG. 3A). A motor 110 arranged below the condensing lens group 111 and the condensing lens 115 rotates the fluorescent wheel 101 .

The fluorescent wheel 101 is formed in a disc shape as shown in FIG. 4( a ), and the center bearing 112 is fixed to the shaft portion of the motor 110 to be rotated by the drive of the motor 110 . The luminescent wheel 101 has a luminescent area 310 and a transmissive area 320 arranged side by side in the circumferential direction. The base material of the fluorescent wheel 101 can be formed of a metal base material such as copper or aluminum. The surface of the substrate on the excitation light irradiation device 70 side is mirror-processed by silver vapor deposition or the like. A green phosphor layer is formed on the mirror-processed surface in the fluorescent emission region 310 . The fluorescence emission region 310 receives blue wavelength band light as excitation light from the excitation light irradiation device 70 and emits fluorescence in the green wavelength band in all directions. A part of the fluorescence is emitted directly to the condenser lens 111 , and the other part is emitted to the condenser lens 111 after being reflected by the reflecting surface of the fluorescence wheel 101 .

Also, the transmissive region 320 of the luminescent wheel 101 can be formed by inserting a translucent transparent base material into a cut-out portion formed in the base material of the luminescent wheel 101 . The transparent base material is made of a transparent material such as glass or resin. Further, the transparent base material may be provided with a diffusion layer on the side irradiated with the blue wavelength band light or on the opposite side thereof. The diffusion layer can be provided, for example, by forming fine unevenness on the surface of the transparent substrate by sandblasting or the like. The blue wavelength band light from the excitation light irradiation device 70 that has entered the transmission region 320 is transmitted or diffusely transmitted through the transmission region 320 and enters the condenser lens 115 .

Returning to FIG. 3 , the condensing lens group 111 converges the luminous flux of the blue wavelength band light emitted from the excitation light irradiation device 70 onto the phosphor wheel 101 and condenses the fluorescence emitted from the phosphor wheel 101 . Condensing lens 115 condenses the ray bundle emitted from luminescent wheel 101 .

The red light source device 120 collects the red wavelength band light emitted from the red light emitting diode 121, which is a semiconductor light emitting element arranged so that the optical axis of the emitted light is parallel to the blue laser diode 71, and the red light emitting diode 121. and a condensing lens group 125 that emits light. The red light source device 120 is arranged such that the optical axis of the red wavelength band light emitted from the red light emitting diode 121 intersects with the optical axis of the green wavelength band light emitted from the phosphor wheel 101 and reflected by the first dichroic mirror 141 . placed in

The light guiding optical system 140 includes a first dichroic mirror 141, a second dichroic mirror 142, a third dichroic mirror 143, condensing lenses 145, 146, 147 for condensing light beams, and converting the optical axis of each light beam. It is composed of a reflecting mirror 144 and the like that have the same optical axis. Each member will be described below.

The first dichroic mirror 141 is arranged between the diffusion plate 79 and the condenser lens group 111 . The first dichroic mirror 141 transmits the blue wavelength band light toward the condenser lens group 111 side and reflects the green wavelength band light toward the condenser lens 145 to convert the optical axis by 90 degrees.

The second dichroic mirror 142 is combining means for combining the green wavelength band light and the red wavelength band light on the same optical axis, reflecting the green wavelength band light and transmitting the red wavelength band light. The green wavelength band light reflected by the first dichroic mirror 141 is condensed by the condensing lens 145 and enters the second dichroic mirror 142 .

The green wavelength band light reflected by the second dichroic mirror 142 is condensed by the condensing lens 146 and enters the third dichroic mirror 143 arranged on the exit side of the condensing lens 146 . The third dichroic mirror 143 reflects red wavelength band light and green wavelength band light and transmits blue wavelength band light. Therefore, the third dichroic mirror 143 reflects the red wavelength band light and the green wavelength band light condensed by the condenser lens 146 to the condenser lens 173, and guides the red wavelength band light and the green wavelength band light. .

Further, when the irradiation position S of the blue wavelength band light on the luminescent wheel 101 is the transmission region 320 (see FIG. 4A), the blue wavelength band light emitted from the blue laser diode 71 is transmitted or diffused through the luminescent wheel 101. After being transmitted and condensed by the condensing lens 115 , the light is guided to the reflecting mirror 144 . The reflecting mirror 144 is arranged on the optical axis of the blue wavelength band light that is transmitted or diffusely transmitted through the luminescent wheel 101 . Reflecting mirror 144 reflects the blue wavelength band light, converts its optical axis by 90 degrees, and guides light to condensing lens 147 . The third dichroic mirror 143 transmits the blue wavelength band light condensed by the condensing lens 147 and guides it toward the condensing lens 173 .

The light source optical system 170 includes a condenser lens 173 , a light tunnel 175 , a condenser lens 178 , an optical axis conversion mirror 181 , a condenser lens 183 , an irradiation mirror 185 and a condenser lens 195 . Note that the condenser lens 195 is also a part of the projection optical system 220 because the image light emitted from the display element 51 arranged behind the condenser lens 195 is emitted toward the projection optical system 220 .

The condenser lens 173 is arranged on the third dichroic mirror 143 side of the light tunnel 175 . The condenser lens 173 collects the green wavelength band light, blue wavelength band light, and red wavelength band light guided from the third dichroic mirror 143 . Each color wavelength band light condensed by the condensing lens 173 is applied to the color wheel 201 of the color wheel device 200 .

The color wheel device 200 includes a color wheel 201 and a motor 210 that drives the color wheel 201 to rotate. The color wheel device 200 is arranged between the condenser lens 173 and the light tunnel 175 so that the optical axis of the ray bundle emitted from the condenser lens 173 and the irradiation surface on the color wheel 201 are perpendicular to each other.

As shown in FIG. 4B, the color wheel 201 is formed in a disc shape, and the bearing 113 at the center is fixed to the shaft of the motor 210 and driven to rotate by the motor 210 . The color wheel 201 has an all-color transmission area 410 and a blue-red transmission area 420 arranged side by side in the circumferential direction. The all-color transmission region 410 is formed of transparent glass or a resin plate, and can transmit light in all wavelength bands including blue wavelength band light, green wavelength band light, and red wavelength band light. Also, the blue and red transmission region 420 may be formed of a color filter to transmit blue wavelength band light and red wavelength band light. The blue wavelength band light, the green wavelength band light, and the red wavelength band light incident on the color wheel 201 are transmitted through the full-color transmission region 410 or the blue-red transmission region 420 and are dimmed, and then enter the light tunnel 175 in FIG. Light is guided toward A ray bundle incident on the light tunnel 175 becomes a ray bundle with a uniform intensity distribution within the light tunnel 175 .

A condenser lens 178 is arranged on the optical axis behind the light tunnel 175 . Further behind the condensing lens 178, an optical axis conversion mirror 181 is arranged. A bundle of rays emitted from the exit port of the light tunnel 175 is condensed by a condensing lens 178 and then reflected toward the left panel 15 by an optical axis conversion mirror 181 .

The ray bundle reflected by the optical axis conversion mirror 181 is condensed by the condensing lens 183, and then irradiated by the irradiation mirror 185 via the condenser lens 195 to the display element 51, which is a DMD, at a predetermined angle.

The light source light applied to the image forming surface of the display element 51 by the light source optical system 170 is reflected by the image forming surface of the display element 51 and projected onto the screen via the projection optical system 220 as projection light. Here, the projection optical system 220 is composed of a condenser lens 195 and a movable lens group and a fixed lens group provided in the lens barrel 230 . The lens barrel 230 is a varifocal lens and is formed so that zoom adjustment and focus adjustment are possible. The movable lens group is formed so as to be movable automatically by the lens motor 45 or manually by the projection image adjusting section 15a.

By configuring the projection device 10 in this way, when the fluorescent wheel 101 and the color wheel 201 are synchronously rotated and light is emitted from the excitation light irradiation device 70 and the red light source device 120 at appropriate timing, green, blue, and red colors are obtained. Light in each wavelength band enters the condenser lens 173 through the light guide optical system 140 and enters the display element 51 through the light source optical system 170 . Therefore, a color image can be projected on the screen by the display element 51 time-divisionally displaying the light of each color according to the data.

FIG. 5 shows the red color in synchronization with the rise timing tup (tup1, tup2, _tup3 ) of the segment switching timing pulse TP from the control unit 38 in the period of the unit image frame T (T ₀ , T ₁ , T 2 . . . ). It is an example of a time chart in which the light source device 60 emits synthetic color light source light by switching each segment of wavelength band light (R), green wavelength band light (G), and blue wavelength band light (B). In FIG. 5, the red light source device 120 (red light emitting diode 121) is R-LED, the excitation light irradiation device 70 (blue laser diode 71) is B-LD, and the fluorescent light emitting region 310 of the fluorescent wheel device 100 (fluorescent wheel 101) is G-FW, the transmission area 320 is indicated by B-FW, the blue and red transmission area 420 of the color wheel device 200 (color wheel 201) is indicated by BR-CW, and the all-color transmission area 410 is indicated by ALL-CW. Here, the red light source device 120 (R-LED), the excitation light irradiation device 70 (B-LD), the fluorescence emission region 310 (G-FW), the transmission region 320 (B-FW), the blue-red transmission region 420 (B ·R-CW) and the height of the all-color transmission region 410 (ALL-CW) schematically indicate the amount of emitted light.

Also, a fixed time from the rising timing tup (tup1, tup2, tup3) of the segment switching timing pulse TP is set as the spoke period Tsp. The timing tup and the spoke period Tsp are set by the timing setting section 53 . In this embodiment, it is set to emit mixed color light in the spoke period Tsp.

For example, in period _T11 , the red light source device 120 (R-LED) that was emitting light in the previous period _T0 begins to extinguish at the rising timing tup1 of the segment switching timing pulse TP. In addition, emission of blue wavelength band light from the excitation light irradiation device 70 (B-LD) is started. As a result, the fluorescence emitting region 310 receives the blue wavelength band light from the excitation light irradiation device 70 as excitation light, and starts emitting fluorescence in the green wavelength band. Meanwhile, the color wheel device 200 switches from the blue-red transmissive region 420 (B·R-CW) to the all-color transmissive region 410 (ALL-CW). The light emitted from the excitation light irradiation device 70 (B-LD) irradiates the fluorescence emitting region 310 (G-FW), and fluorescence in the green wavelength band light is emitted. However, the red wavelength band light (the red wavelength band light from the red light source device 120 (R-LED) and the green wavelength band light from the fluorescence emission region 310 (G-FW) is transmitted through the blue-red transmission region 420 (B R- CW), the irradiation spot of the light source light (the light of the red component extracted by passing through the CW) extends from the blue-red transmission region 420 (BR-CW) to the all-color transmission region 410 (ALL-CW), and gradually changes to red. The ratio of wavelength band light changes. Therefore, the red wavelength band light (the red wavelength band light from the red light source device 120 (R-LED) and the green wavelength band light from the fluorescence emission region 310 (G-FW) is transmitted from the blue-red transmission region 420 (B R- The light amount of the red component light extracted through the CW) decreases, and the light amount of the green wavelength band light passing through the all-color transmission region 410 (ALL-CW) increases. Therefore, the spoke period Tsp of the period _T11 is a color mixture period in which the red wavelength band light and the green wavelength band light are mixed to emit the yellow wavelength band light (Y). If the spoke period of the yellow wavelength band light (Y) is 6 degrees, it is desirable that the amount of light from the red light source device 120 (R-LED) at the point of 3 degrees is half the value when it is lit. After the spoke period Tsp of the period _T11 has passed, the red light source device 120 (R-LED) is completely extinguished, and the color wheel 201 changes from the blue-red transmission area 420 (B/R-CW) to the all-color transmission area 410. (ALL-CW) completely. Then, the light source device 60 emits green wavelength band light (G).

In period _T12 , at the rising timing tup2, the driving current value of the excitation light irradiation device 70 (B-LD) is increased, and the amount of blue wavelength band light emitted from the excitation light irradiation device 70 (B-LD) is increased. The amount of light is increased. On the other hand, the fluorescent wheel 101 switches from the fluorescent emission area 310 (G-FW) to the transmission area 320 (B-FW). Therefore, the spoke period Tsp of the period _T12 is a color mixture period in which the blue wavelength band light and the green wavelength band light are mixed and cyan wavelength band light (CY) is emitted. After the spoke period Tsp of period _T12 has elapsed, blue wavelength band light (B) is emitted. Note that the color wheel 201 shifts from the all-color transmission region 410 (ALL- _CW ) to the blue-red transmission region 420 (B·R- CW).

In the period _T13 , the red light source device 120 (R-LED) starts lighting at the timing of the rising timing tup3. On the other hand, the excitation light irradiation device 70 (B-LD) begins to turn off. Therefore, in the spoke period Tsp of the period _T13 , the red wavelength band light (the red wavelength band light from the red light source device 120 (R-LED)) and the blue wavelength band light transmitted through the transmission region 320 (B-FW) , are mixed to emit magenta wavelength band light (MG), and the color mixing period is set. After the spoke period Tsp of the period _T13 has passed, the red wavelength band light (R) is emitted.

In the time chart of FIG. 5, the current value is decreased while the excitation light irradiation device 70 irradiates the fluorescence emission region 310, but the current value is increased while the fluorescence emission region 310 is irradiated. It may also be set to lower the current value while transmitting through the transmissive region 320 .

The projection apparatus 10 can be in a “brightness-oriented” color mode that brightens the projected light by using the yellow wavelength band light (Y) in the spoke period Tsp in the period _T11 , for example. Further, for example, if the timing of switching from the all-color transmission region 410 (ALL-CW) to the blue-red transmission region 420 (B·R-CW) in the period _T12 is matched with the timing tup3, the blue wavelength band light is transmitted to the all-color transmission region 410 A “color-focused mode” in which only (ALL-CW) is transmitted and the emission period of the red wavelength band light is increased can also be set. In addition, various color modes can be set by adjusting the amount of light by adjusting the drive current values of the blue laser diode 71 and the red light emitting diode 121 .

Here, the amount of light of the semiconductor light-emitting elements such as the red light-emitting diode 121 and the blue laser diode 71 gradually increases or decreases when they are lit or when the drive current increases, or when they are extinguished or the drive current decreases. This is because these semiconductor light emitting devices emit light with an amount of light corresponding to the current value, but have current rising (current falling) characteristics until the current value reaches the target current value and stabilizes. .

6A to 6C schematically show an example of the rising waveform (light source current waveform) of the blue laser diode 71. FIG. Such a rising waveform of the blue laser diode 71 is, in _FIG . 70 (B-LD) is increased to increase the amount of blue wavelength band light emitted from the excitation light irradiation device ₇₀ (B-LD). is.

The vertical axis represents the current value for driving the blue laser diode 71, and the horizontal axis represents time (spoke period Tsp). As shown in FIG. 6A, the blue laser diode 71 is represented by changing portions _I11 , _I21 , and _I31 in which the current value changes until reaching the target current values _I12 , _I22 , and _I32 . waveform characteristics. FIGS _. 6A to 6C _show current waveforms I ₁ , I ₂ , and _{I 3} corresponding to various color modes. Three target current values I ₁₂ , I ₂₂ , and I ₃₂ are shown in descending order of .

The amount of light from the blue laser diode 71 is calculated from the current value and time. The amount of light is calculated by detecting the current value of the blue laser diode 71 by the detector 56 . Therefore, as shown in FIG. 6A, when the current value fluctuates due to a change in color mode, the amount of light in the spoke period Tsp changes. Then, if the projection image emitted via the projection optical system 220 has gradation, discontinuous points may be seen in the gradation. Therefore, for each color mode in which the current value fluctuates, the timing of the rise (or fall) of the current value is adjusted. By uniforming the ratio, it is possible to maintain the reproducibility of the gradation even if the color mode is changed.

Delay adjustment is performed according to the flowchart of FIG.
Step S001: When the delay adjustment is started, first, the spoke period Tsp is divided into three by the delay time setting unit 54 as shown in FIG. 6(a). Here, it is divided into three periods Tsp1, Tsp2, and Tsp3. For example, when the spoke period Tsp is set at 17 degrees, it is divided into Tsp1=6 degrees, Tsp2=6 degrees, and Tsp3=7 degrees.

Step S002; Next, an image with gradation is projected onto the screen via the projection optical system 220, and the gradation is visually confirmed.
Steps S003 and S004: If the gradations are unnaturally continuous, the delay time setting unit 54 changes the divided spoke periods Tsp1, Tsp2, and Tsp3 as shown in FIG. , the color of the spoke period Tsp is set so that the changing portions I ₁₁ , I ₂₁ , and I ₃₁ of the current waveform are closer to the central portion of the spoke period Tsp (that is, the period Tsp2).

Step S005: The delay time setting unit 54 sets the delay time between the minimum and maximum currents (that is, the red wavelength band light and the green wavelength band light are mixed and emitted during the spoke period Tsp of the color wheel 201). shift the start timing of the color mixing period). For example, in the example of FIG. 6C, the current waveform _I1 with the highest target current value _I12 has a delay time Δt1, the current waveform _I2 with an intermediate target current value _I22 has a delay time Δt2, and the target The current waveform _I3 with the lowest current value _I32 sets the delay time to Δt3.

In this way, as shown in FIG. 6(c), regardless of whether the target current values _I12 , _I22 , _I32 are high or low, the current waveforms _I1 , _I2 , _I3 over the period Tsp1 to the period Tsp3 can be made substantially constant. The light source driving section 55 drives the light source device 60 (light source section) via the light source control circuit 41 based on the settings of the timing setting section 53 and the delay time setting section 54 . Therefore, the image projected in this way maintains the reproducibility of gradation even if the color mode is changed.

In the present embodiment, information indicating the amount of blue light emitted from the projection optical system 220 during the spoke period Tsp is detected by the detection unit 56 measuring the current value of the blue laser diode 71. For example, the detection unit may include an illuminance sensor to measure the illuminance of the projected image and detect information indicating the amount of light of each color. Further, in this embodiment, delay adjustment for the blue laser diode 71 has been described, but delay adjustment for the red light emitting diode 121 can also be performed.

The delay time setting between the minimum and maximum currents by the delay time setting unit 54 can also be a lookup table stored in a storage unit such as an S-RAM connected to the control unit 38 .

As described above, according to the embodiment of the present invention, the projection device 10 includes the excitation light irradiation device 70 (blue laser diode 71) and the color wheel device 200 (color wheel 201). (first wavelength band light) and green wavelength band light (second wavelength band light) from the luminescent wheel device 100. Based on the index related to the brightness of the emitted light, the red wavelength band light and the green wavelength band light are mixed during the spoke period Tsp of the color wheel 201, which is the emission switching timing of the red wavelength band light and the green wavelength band light. A delay time setting unit 54 for shifting the start timing of the color mixture period emitted by the light source 100 and a light source driving unit 55 for driving the light source device 60 based on the setting of the delay time setting unit 54 are provided. Accordingly, it is possible to provide the projection device 10 that can maintain the reproducibility of the gradation even if the color mode is changed.

Also, the spoke period Tsp is divided into three. Thus, the spoke period Tsp can be changed by switching the delay adjustment in conjunction with the color mode.

Further, the delay time setting unit 54 shifts the change portions _I11 , _I21 , and _I31 of the information indicating the light amount of each color light (that is, the index related to the brightness of the light) to the central portion of the three-divided spoke period Tsp. The delay time (shifting the start timing of the color mixture period) is set in this way. As a result, the number of man-hours for calibration during the spoke period (period Tsp3) in which the blue laser diode 71 does not fluctuate can be reduced.

In addition, the light brightness index includes the drive current or temperature of the blue laser diode 71 . As a result, even if the driving current value of the blue laser diode 71 and the temperature due to the use of the blue laser diode 71 change, the gradation reproducibility can be maintained.

Further, the delay time setting unit 54 sets switching timings of the plurality of lights emitted by the light source device 60 for each of the plurality of color modes. As a result, the reproducibility of gradation can be maintained even in the color mode in which the light switching timing changes.

The color mode includes a brightness-oriented mode that emphasizes the brightness of the projected image and a color-oriented mode that emphasizes the color tone of the projected image. As a result, a clear projected image can be obtained even in a bright room, and a projected image suitable for watching movies can be obtained.

The start timing of the color mixture period is set between the lowest current value and the highest current value of the drive current for the blue laser diode 71 . As a result, it is possible to provide the projection device 10 in which the gradation does not fluctuate depending on the value of the current flowing through the light source, and the range of current values in which the reproducibility of gradation can be maintained is wider than in the past.

The delay time of the light emission timing of the light source unit set by the delay time setting unit is based on the brightness index. It may be based on
If the delay time of the light emission timing of the light source unit set by the delay time setting unit is based on an index related to brightness, information indicating the light amount of each color light (the blue laser diode 71, which is a semiconductor light emitting element) may be set based on other factors than the current value of the driving current of , and the brightness set by the user).

For example, since the semiconductor light emitting element generates heat and changes in temperature as the projection apparatus is used, the delay time may be set according to the temperature of the semiconductor light emitting element. Thus, the delay time setting unit can set the delay time every predetermined time (for example, every 100 microseconds) based on various indices related to brightness.

Also, the control unit 38 of the projection device 10 serving as a projection control device includes a delay time setting unit 54 and a light source driving unit 55 . The control unit 38 functions as a delay time setting unit 54 and a light source driving unit 55 by a program stored in a storage unit such as an S-RAM connected to the control unit 38 . As a result, it is possible to provide a projection control apparatus and a program capable of maintaining gradation reproducibility even when the color mode is changed.

While several embodiments of the invention have been described, these embodiments have been presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, replacements, and modifications can be made without departing from the scope of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are included in the scope of the invention described in the claims and its equivalents.

Below, the invention described in the first claim of the present application is added.
[1] A light source unit that includes a semiconductor light emitting element and a color wheel and emits light of a plurality of colors including first wavelength band light and second wavelength band light in a time division manner;
a display element irradiated with light source light from the light source unit and forming image light;
a projection optical system that projects the image light emitted from the display element onto a projection target;
The first wavelength band light in the spoke period of the color wheel, which is the emission switching timing of the first wavelength band light and the second wavelength band light, based on an index related to the brightness of the light emitted from the light source unit. and a delay time setting unit that shifts the start timing of a color mixing period in which the light of the second wavelength band is mixed and emitted;
a light source driving unit that drives the light source unit based on the setting of the delay time setting unit;
A projection device comprising:
[2] The projection device according to [1], wherein the spoke period is divided into three.
[3] The delay time setting unit sets the start timing of the color mixture period so that the changing portion of the index related to the brightness of the light is near the center of the spoke period divided into three. The projection device according to [2] above.
[4] The projection apparatus according to any one of [1] to [3], wherein the index related to the brightness of the light includes driving current or temperature of the semiconductor light emitting device.
[5] Any one of [1] to [4], wherein the delay time setting unit sets switching timings of the light of a plurality of colors emitted by the light source unit for each of a plurality of color modes. projection device.
[6] The projection apparatus according to [5], wherein the color mode includes a brightness mode that emphasizes the brightness of the projected image, and a color-oriented mode that emphasizes the color tone of the projected image.
[7] The projection apparatus according to [4], wherein the start timing of the color mixture period is set between the lowest current value and the highest current value of the drive current.
[8] Based on an index related to the brightness of light emitted from a light source unit that includes a semiconductor light emitting element and a color wheel and emits light of a plurality of colors including the first wavelength band light and the second wavelength band light in a time division manner The first wavelength band light and the second wavelength band light are mixed and emitted in the spoke period of the color wheel, which is the emission switching timing of the first wavelength band light and the second wavelength band light. a delay time setting unit that shifts the start timing of the color mixing period;
a light source driving unit that drives the light source unit based on the setting of the delay time setting unit;
A projection control apparatus comprising:
[9] A program executed by a computer, comprising:
Based on the index related to the brightness of light emitted from a light source unit that includes a semiconductor light emitting element and a color wheel and emits light of a plurality of colors including the first wavelength band light and the second wavelength band light in a time division manner, A color mixing period in which the light of the first wavelength band and the light of the second wavelength band are mixed and emitted in the spoke period of the color wheel, which is the timing of switching the light emission of the light of the first wavelength band and the light of the second wavelength band. a delay time setting unit that shifts the start timing;
a light source driving unit that drives the light source unit based on the setting of the delay time setting unit;
A program characterized by functioning as

REFERENCE SIGNS LIST 10 projection device 15 left panel 15a projection image adjustment unit 21 input/output connector unit 22 input/output interface 23 image conversion unit 24 display encoder 25 video RAM
26 display driving unit 31 image compression/decompression unit 32 memory card 35 Ir reception unit 36 Ir processing unit 37 key/indicator unit 38 control unit 41 light source control circuit 43 cooling fan drive control circuit 45 lens motor 47 audio processing unit 48 speaker 51 display Element 53 Timing setting unit 54 Delay time setting unit 55 Light source driving unit 56 Detecting unit 60 Light source device 70 Excitation light irradiation device 71 Blue laser diode 73 Collimator lens 77 Condensing lens 78 Condensing lens 79 Diffusion plate 80 Green light source device 100 Fluorescent wheel Device 101 fluorescent wheel 110 motor 111 condenser lens group 111 condenser lens 112 bearing 113 bearing 115 condenser lens 120 red light source device 121 red light emitting diode 125 condenser lens group 140 light guide optical system 141 first dichroic mirror 142 second dichroic Mirror 143 Third dichroic mirror 144 Reflecting mirror 145 Condensing lens 146 Condensing lens 147 Condensing lens 170 Light source optical system 173 Condensing lens 175 Light tunnel 178 Condensing lens 181 Optical axis conversion mirror 183 Condensing lens 185 Irradiation mirror 195 Condenser Lens 200 Color wheel device 201 Color wheel 210 Motor 220 Projection optical system 230 Lens barrel 310 Fluorescence emission area 320 Transmission area 410 Full color transmission area 420 Blue-red transmission area

Claims (10)

a light source unit that includes a semiconductor light emitting element and a color wheel and emits light of a plurality of colors including the first wavelength band light and the second wavelength band light in a time division manner;
a display element irradiated with light source light from the light source unit and forming image light;
a projection optical system that projects the image light emitted from the display element onto a projection target;
The first wavelength band light in the spoke period of the color wheel, which is the emission switching timing of the first wavelength band light and the second wavelength band light, based on an index related to the brightness of the light emitted from the light source unit. and a delay time setting unit that shifts the start timing of a color mixing period in which the light of the second wavelength band is mixed and emitted;
a light source driving unit that drives the light source unit based on the setting of the delay time setting unit;
has
the spoke period is divided into a plurality,
The delay time setting unit sets the start timing of the color mixture period so that the changing portion of the index related to the brightness of the light is shifted to one of the spoke periods divided into a plurality of spoke periods. . When the gradation image projected onto the projection medium via the projection optical system has an unnatural continuation, the delay time setting unit sets the spoke period in which the changing portion of the current waveform is divided into a plurality of parts. 2. The projection apparatus according to claim 1, wherein the color of the spoke period is set by varying the spoke period divided into a plurality of spoke periods so as to lean towards one of them. 3. The projection apparatus according to claim 2, wherein the delay time setting unit sets the delay time of the current waveform differently depending on the target current value . the first wavelength band light is red wavelength band light,
4. The projection apparatus according to claim 1, wherein said second wavelength band light is green wavelength band light. 5. The projection apparatus according to any one of claims 1 to 4 , wherein the index relating to the light brightness includes driving current or temperature of the semiconductor light emitting device. 6. The projection apparatus according to any one of claims 1 to 5, wherein the delay time setting section sets switching timings of light of a plurality of colors emitted by the light source section for each of a plurality of color modes. 7. The projection apparatus according to claim 6, wherein the color mode includes a brightness mode that emphasizes the brightness of the projected image and a color-oriented mode that emphasizes the color tone of the projected image. 6. The projection apparatus according to claim 5, wherein the setting of the start timing of the color mixing period is performed between the lowest current value and the highest current value of the drive current. Based on the index related to the brightness of light emitted from a light source unit that includes a semiconductor light emitting element and a color wheel and emits light of a plurality of colors including the first wavelength band light and the second wavelength band light in a time division manner, A color mixing period in which the light of the first wavelength band and the light of the second wavelength band are mixed and emitted in the spoke period of the color wheel, which is the timing of switching the light emission of the light of the first wavelength band and the light of the second wavelength band. a delay time setting unit that shifts the start timing;
a light source driving unit that drives the light source unit based on the setting of the delay time setting unit;
has
the spoke period is divided into a plurality,
The projection control according to claim 1, wherein the delay time setting unit sets the start timing of the color mixture period so that the changing portion of the index related to the brightness of the light is shifted to one of the spoke periods divided into a plurality of spoke periods. Device. A program executed by a computer, the computer comprising:
Based on the index related to the brightness of light emitted from a light source unit that includes a semiconductor light emitting element and a color wheel and emits light of a plurality of colors including the first wavelength band light and the second wavelength band light in a time division manner, A color mixing period in which the light of the first wavelength band and the light of the second wavelength band are mixed and emitted in the spoke period of the color wheel, which is the timing of switching the light emission of the light of the first wavelength band and the light of the second wavelength band. a delay time setting unit that shifts the start timing;
a light source driving unit that drives the light source unit based on the setting of the delay time setting unit;
function as
the spoke period is divided into a plurality,
The program, wherein the delay time setting unit sets the start timing of the color mixing period so that the changing portion of the index related to the brightness of the light is shifted to one of the spoke periods divided into a plurality of spoke periods. .

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