JP2013235273A - Projection apparatus, projection method, and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress influence due to heat fluctuation of a light source, and to maintain quality of a projected image at high state.SOLUTION: A projection apparatus comprises: an LED array 17 which is a light source capable of emitting light by adjusting luminance of light emitting elements in a plurality of colors by every color; projection systems 13 to 16 and 18 to 21 which project color images of one frame by forming optical images by unit of field period by every color component by a color sequential system by using light from the LED array 17; and light source control systems 27 to 29, 25, and 22 to 24 which adjust brightness of the light emitting elements in each color of the LED array 17 on the basis of supply power waveform information for offsetting brightness fluctuation in each field period by every color component with respect to the LED array 17.

Description

  The present invention relates to a projection apparatus, a projection method, and a program suitable for a projector apparatus using a light emitting diode or the like as a light source.

  Various projector devices that can be recognized as color images on human vision by switching multiple color images at high speed and projecting them continuously, called color sequential method or field sequential method Planned and commercialized.

In this type of projector apparatus, particularly with an LED as the light source, a plurality of R (red), G (green), and B (blue) color LEDs serving as the light source are simultaneously used for the purpose of securing the amount of light. A technique for lighting is considered. (For example, Patent Document 1)
FIG. 7 illustrates the light emission luminance of a red LED (hereinafter “R-LED”) when one image frame is divided into three fields for projecting RGB color images. FIG. 7A shows the formation timing (field) of each color image in a DMD (Digital Micromirror Device) (registered trademark), which is an element that forms an optical image to be projected.

  FIG. 7 (2) shows current values set to flow through the R-LED for each of the R, G, and B fields. As shown in FIG. 2 (2), in the R field, a full level current value flows through the R-LED, while in the subsequent G field, a current value of a level larger than the full level half value flows through the R-LED. You can see that

  On the other hand, the light quantity of the red light actually emitted from the R-LED as the light source is shown in FIG. As shown in FIG. 3 (3), during the R field period, a full-level current value flows, so that the LED generates heat, and as a result, the light emission amount rapidly decreases immediately after lighting, and thereafter the decrease amount gradually. Gradually decreases.

  In the subsequent G field, the set current value is greatly reduced from the full level, so that the light emission amount is greatly reduced immediately after the field switching. Thereafter, the light emission amount gradually increases as the heat generation amount in the R-LED decreases due to the decrease in the set current value.

  In the subsequent B field, since the set current value of the R-LED is set to “0 (zero)”, the light emission amount is also set to “0”.

  Although not shown, other green (G) LEDs and blue (B) LEDs serving as light sources also vary in actual light emission amount due to heat generation with respect to the set current value.

  This is not limited to the case where an LED is used as a light source, but the same applies to a case where a semiconductor laser is used as a light source, for example, and the amount of light emission varies in each field even when driven at a set current value due to the influence of heat generation. .

Japanese Patent No. 3781743

  As described above, in a projector apparatus using an LED, a semiconductor laser, or the like as a light source, even if the light source is driven with a preset power, the light emission amount fluctuates due to the influence of heat generated by the light source, resulting in a decrease in the quality of the projected image. There is a problem that.

  The present invention has been made in view of the above circumstances, and the object of the invention is a projection apparatus capable of suppressing the influence of thermal fluctuations of the light source and maintaining the quality of the projected image in a high state, To provide a projection method and a program.

The present invention provides a plurality of light emitting elements that respectively emit light of different colors, a projecting unit that sequentially forms and projects a light image of an image of a plurality of color components for each frame, and a luminance based on heat generation of the light emitting elements. Light source control means for adjusting power supplied to the light emitting element so as to correct the decrease, selection means for selecting one projection color mode from a plurality of projection color modes, and reduction in luminance due to heat generation of the light emitting element. Storage means for storing power information to be corrected in advance, wherein the storage means stores in advance the power information based on each of the plurality of projection color modes, and the light source control means is the selection means. The power supplied to the light emitting element is adjusted based on the selected projection color mode.

  According to the present invention, it is possible to suppress the influence due to the heat fluctuation of the light source and maintain the quality of the projected image in a high state.

1 is a block diagram showing a schematic configuration of a functional circuit of a data projector device according to a first embodiment of the present invention. The figure which shows the control principle of the electric current value adjustment waveform which concerns on the same embodiment. 6 is a flowchart showing the processing content of a projection operation including current value waveform adjustment according to the embodiment. The figure which shows the control operation example of the electric current value adjustment waveform which concerns on the same embodiment. The block diagram which shows schematic structure of the functional circuit of the data projector apparatus which concerns on the 2nd Embodiment of this invention. 6 is a flowchart showing the processing content of a projection operation including current value waveform adjustment according to the embodiment. The figure which shows the relationship between the drive current value and light emission amount by a general LED light source.

(First embodiment)
A first embodiment when the present invention is applied to a data projector apparatus using an LED as a light source will be described below with reference to the drawings.

FIG. 1 is a block diagram showing a schematic functional configuration of an electronic circuit included in the data projector device 10 according to the embodiment.
An input / output connector unit 11 includes, for example, a pin jack (RCA) type video input terminal, a D-sub15 type RGB input terminal, and a USB (Universal Serial Bus) connector.

  Image signals of various standards input from the input / output connector unit 11 are input to an image conversion unit 13 that is also generally referred to as a scaler via an input / output interface (I / F) 12 and a system bus SB. The image conversion unit 13 unifies the input image signal into an image signal of a predetermined format suitable for projection, and appropriately stores it in the video RAM 14 which is a buffer memory for display, and then sends it to the projection image processing unit 15.

  At this time, data such as symbols indicating various operation states for OSD (On Screen Display) is also superimposed on the image signal by the video RAM 14 as necessary, and the processed image signal is sent to the projection image processing unit 15.

  The projection image processing unit 15 multiplies a frame rate according to a predetermined format, for example, 60 [frames / second], the number of color component divisions, and the number of display gradations, in accordance with the transmitted image signal. The micromirror element 16, which is a spatial light modulation element (SOM), is driven to display by high-speed time division driving.

  The micromirror element 16 is turned on / off individually at a high speed by tilting angles of a plurality of micromirrors arranged in an array, for example, XGA (horizontal 1024 × vertical 768 dots). Form an image.

  On the other hand, the LED array 17 is used as a light source of the data projector device 10. The LED array 17 is configured in an array so that a large number of LEDs that emit light of RGB colors are regularly mixed.

  The time-divided light emission for each color component of the LED array 17 is collected by a truncated pyramid-shaped housing 18 having a reflecting mirror pasted on the entire inner surface, and is converted into a luminous flux with a uniform luminance distribution by an integrator 19. The micromirror element 16 is irradiated with total reflection.

  Then, an optical image is formed by the reflected light from the micromirror element 16, and the formed optical image is projected and displayed via a projection lens unit 21 on a screen (not shown) to be projected.

  In the LED array 17, LED groups of corresponding colors are driven and controlled by the R driver 22, the G driver 23, and the B driver 24, respectively, and each primary color of RGB emits light in a time division manner.

  The projection light processing unit 25 includes a current control unit 25a, and controls the light emission timing and driving current by the R driver 22, G driver 23, and B driver 24 according to the image data given from the projection image processing unit 15. .

  Further, the projection light processing unit 25 receives each detection signal from illuminance sensors 26R, 26G, and 26B that detect the brightness of each color of the light image formed by the micromirror element 16 for each color. The current control unit 25a controls each current value supplied to the R driver 22, G driver 23, and B driver 24 and the waveform thereof based on the brightness detected by the illuminance sensors 26R, 26G, and 26B.

  The CPU 27 controls all the operations of the above circuits. The CPU 27 is connected to the main memory 28 and the program memory 29. The main memory 28 is composed of a DRAM and functions as a work memory. The program memory 29 is configured by an electrically rewritable nonvolatile memory that stores an operation program, various types of fixed data, and a plurality of current waveform information for LED driving described later. The CPU 27 uses the main memory 28 and the program memory 29 to execute the overall control operation in the data projector apparatus 10.

  The CPU 27 executes various projection operations according to key operation signals from the operation unit 30. The operation unit 30 includes a key operation unit provided in the main body of the data projector device 10 and a laser light receiving unit that receives infrared light from a remote controller (not shown) dedicated to the data projector device 10. The operation unit 30 directly outputs a key operation signal based on keys operated by the user directly or via a remote controller to the CPU 27.

  The CPU 27 is further connected to an audio processing unit 31 and a wireless LAN interface (I / F) 32 via the system bus SB.

  The sound processing unit 31 includes a sound source circuit such as a PCM sound source, converts the sound data given during the projection operation into an analog signal, drives the speaker unit 33 to emit a loud sound, or generates a beep sound or the like as necessary.

  The wireless LAN interface 32 transmits / receives data to / from an external device (not shown) such as a personal computer using a 2.4 [GHz] band radio wave in accordance with, for example, the IEEE 802.11b / g standard via the wireless LAN antenna 34.

Next, the operation of the above embodiment will be described.
First, the basic concept of control in this embodiment will be described with reference to FIG.
FIG. 2 exemplifies the light emission luminance of a red LED (hereinafter “R-LED”) that constitutes a part of the LED array 17 when one image frame is divided into three fields for projecting RGB color images. FIG. 2 (1) shows the formation timing (field) of each color image in the micromirror element 16.

  FIG. 2 (2) shows a reference current value set to flow through the R-LED for each of the R, G, and B fields. As shown in FIG. 2B, in the R field, a full-level current value flows through the R-LED, while in the subsequent G field, a current value of a level larger than the half-value of the full level flows through the R-LED. Recognize.

  In this way, even in the G and B fields where the R-LED is not normally lit, the R-LED is lit by changing the current value, so that high luminance can be obtained and the color can be adjusted. Further, the same lighting control is performed for the G-LED and B-LED.

  On the other hand, the waveform of the current value that the R driver 22 actually supplies to the R-LED that is the light source is shown in FIG. As shown in FIG. 3 (3), in consideration of the amount of light that would decrease due to heat generated by the R-LED in advance, for example, in the R field, in addition to the original current value shown in FIG. 2 (2), The waveform i1 is obtained by increasing the current value by the amount of the reduced light amount.

  In the subsequent G field, in addition to the original current value, the current value is controlled as much as possible to obtain a waveform i2 in which the current value is increased by the amount of the reduced light.

  Further, the data projector device 10 of the present invention, for example, continuously heats the R-LED by changing the current value for each of the R, G, and B fields. Therefore, the R, G, and B fields generate heat. The amount inherits the effect of heat generated in the previous field, and the current value waveform shown in FIG. 2 (3) is a current value waveform adjusted in consideration of the effect of the inherited heat value. is there.

  These current waveforms are read out from the standard data stored in advance in the program memory 29 by the CPU 27, expanded and stored in the main memory 28, and then sent to the projection light processing unit 25 and sent out by the current control unit 25a. This is realized by controlling the drive current value in the R driver 22.

  FIG. 2 (4) shows the actual amount of red light emitted from the R-LED as a result of driving the R-LED with the current value of the waveform as described above. As shown in FIG. 4 (4), in each of the R, G, and B field periods, the influence of heat generation can be offset and a constant light amount can be maintained during each period.

  In this way, driving with a current value having a waveform that cancels the reduction in the amount of light due to the heat generated by the LED, as a result, the LED can be driven to emit light with a stable amount of light in each field period.

  The above-described control is performed not only on the R-LEDs constituting part of the LED array 17 but also on G (green) -LEDs and B (blue) -LEDs.

  In addition, the current value waveforms for the R, G, and B LEDs differ depending on the projection color mode described below. That is, in the program memory 29, information on current value waveforms for driving the R, G, and B LEDs for each of a plurality of projection color modes is stored in advance as data.

  That is, for example, when a projection color mode such as “theater mode” that emphasizes color or “presentation mode” that emphasizes luminance is prepared in advance so as to be selectable, the current value waveform stored in the program memory 29 is “ The “presentation mode” is adjusted to obtain a higher luminance than the “theater mode”.

  Next, a projection operation of the data projector device 10 mainly for controlling the R, G, and B LED groups constituting the LED array 17 will be described with reference to FIG.

  FIG. 3 shows a part of the projection operation that is executed after the CPU 27 reads out the operation program stored in the program memory 29, develops it, and stores it in the main memory 28 after the power of the data projector apparatus 10 is turned on. Is shown.

  Initially, before projecting the input image, various projection color mode names indicating the relationship between the color and brightness of the entire projected image, such as “theater mode” and “presentation mode”, are projected as a list image (steps). S101).

  For this projection, it is determined whether or not an operation for selecting any one of the projected modes has been performed by the operation unit 30 (step S102), and if not operated, the process returns to step S101 again. In this way, the processes in steps S101 and S102 are repeated, and while the list projection of the projection color modes is performed, it waits for one of these modes to be selected.

  When one of the color modes is selected, the operation is determined in step S102, and information on the current value waveform for each of the R, G, B color LEDs corresponding to the selected mode is alternatively selected from the program memory 29. (Step S103), stored in the main memory 28, and set in the current control unit 25a of the projection light processing unit 25 to control the R driver 22, G driver 23, and B driver 24 (step S103). Step S104).

  As described above, the information on the current value waveform is a value stored in advance so as to cancel out the light amount decrease caused by the heat generation of the LED at the start of projection.

  After the setting, the LED array 17 is driven by the R driver 22, the G driver 23, and the B driver 24 according to the current value waveform set in the current control unit 25 a, via the input / output connector unit 11 or the wireless LAN antenna 34. The projection operation of the input image signal is started (step S105).

  Here, when performing the continuous projection operation of the data projector device 10, as described above, the amount of heat generated in each field of the LED light source is affected by the heat generated in the previous field, and therefore passes through the projection frame. It gradually accumulates.

  Therefore, in step S104, the amount of heat generated in each field by the continuous projection operation is set despite the fact that the current value waveform that cancels the decrease in the amount of light caused by the LED heat generation is set in the R driver 22 to control the lighting of each LED. Due to the accumulation, the amount of light further decreases, and even if the current value waveform set in step S104 is used, the decrease in the amount of light may not be offset.

  Therefore, it is necessary to reset the current value waveform in the current control unit 25a so as to readjust the further decrease in the light amount due to the accumulation of the calorific value at regular intervals, for example, as the projection operation continues. There is.

  Therefore, in accordance with the start of the projection operation, the CPU 27 causes the timer to set a time for counting in the main memory 28 (step S106). This timer counts a fixed time T, for example, 30 [minutes] as the measurement interval of the thermal fluctuation accompanying the progress of the projection operation occurring in each LED group of the R, G, B constituting the LED array 17 as described above. It is. It is determined whether or not the count value has reached a certain value T as the timer counts (step S107).

  Here, if the count value of the timer has not reached the constant value T, the process returns to the process from step S106 again. Thereafter, the above-described steps S106 and S107 are repeatedly executed while performing the projection operation, thereby waiting for the count value of the timer to reach a constant value T.

  When the count value of the timer becomes a constant value T, it is determined in step S107, and the illuminance sensor 26R, R, G, B for each LED group constituting the LED array 17 at that time is determined. The illuminance is measured with 26G and 26B (step S108).

  In this illuminance measurement, the light image formed by the micromirror element 16 is set to full gradation for all the R, G, and B light images for one frame or two frames in accordance with the measurement timing. It may be. Even if only one frame or two frames out of 60 frames per second are projected in full gradation in this way, even in a situation where the human eye can hardly perceive and the projected image quality deteriorates. It does n’t come.

  As a result of the measured illuminance, the projection light processing unit 25 determines whether there is a deviation from the set illuminance for each of the R, G, and B LED groups (step S109).

  If it is determined that there is no deviation between the two illuminances in any of the R, G, and B LED groups, the timer count value is cleared as it is (step S112), and then the above step is performed again. The process returns to S106.

  If it is determined in step S109 that there is a deviation of a predetermined value or more between the illuminance obtained as a result of the measurement and the set illuminance, then a current value adjustment waveform that gives the desired illuminance in consideration of the deviation. Is calculated (step S110).

  Thereafter, information corresponding to the calculated current value adjustment waveform is read from the program memory 29 and reset in the current control unit 25a of the projection light processing unit 25 (step S111).

  FIG. 4 illustrates the light emission luminance of a red LED (hereinafter referred to as “R-LED”) constituting a part of the LED array 17 over a period of two frames before and after the processing of steps S110 and S111. FIG. 4A shows the formation timing (field) of each color (R, G, B) image in the micromirror element 16.

  FIG. 4 (2) shows a reference current value for obtaining a target light amount set to flow to the R-LED for each of the R, G, and B fields through two frames. As shown in FIG. 2B, in the R field, a full-level current value flows through the R-LED, while in the subsequent G field, a current value of a level larger than the half-value of the full level flows through the R-LED. Recognize.

  On the other hand, the waveform of the current value that the R driver 22 actually supplies to the R-LED that is the light source is shown in FIG. In the first frame of FIG. 3 (3), in consideration of the amount of light that would decrease due to heat generated by the R-LED, in addition to the original current value shown in FIG. The waveform i1 is obtained by increasing the current value by the amount of the decreased light amount. In the subsequent G field, in addition to the original current value, the current value is controlled as much as possible to obtain a waveform i2 in which the current value is increased by the amount of the reduced light.

  The current waveform information is sent to the projection light processing unit 25 after the CPU 27 reads out the standard data stored in the program memory 29 and develops and stores it in the main memory 28. The current control unit 25a of the projection light processing unit 25 controls the drive current value in the R driver 22 based on this waveform information.

  Furthermore, the illuminance actually obtained by the illuminance sensor 26R is shown in FIG. Looking at the illuminance measured in the first frame of FIG. 4 (4), the G field was lit with the current value waveform shown in FIG. 4 (3) set to offset the decrease in the amount of light due to heat generation. Nevertheless, when the illuminance lower by ΔL1 than the target illuminance is measured due to the accumulation of the heat generation amount of the LED as the projection operation proceeds as described above, the target illuminance set in step S104 is In step S110, a current value adjustment waveform i3 that further cancels out the light amount decrease of ΔL1 is calculated.

  Then, in the next step S111, in addition to the current value supplied in the first frame of FIG. 4 (3), the current value adjustment waveform calculated so as to cancel out the further light amount decrease is controlled by the current control of the projection light processing unit 25. By resetting the unit 25a and controlling the R driver 22, in the second and subsequent frames, the illuminance deficiency of ΔL1 in the G field is resolved, and the R-LEDs of the LED array 17 with the illuminance as set. Can be turned on.

  The above control is executed not only for the R-LEDs constituting part of the LED array 17 but also for the G-LEDs and B-LEDs.

  After the process of step S111, after clearing the count value of the timer in step S112, the process returns to the process from step S106 again.

  Thus, as described in detail, according to the present embodiment, the projection lens unit 21 projects the image by suppressing the influence of thermal fluctuations of the R, G, and B LED groups constituting the LED array 17 serving as the light source. It is possible to maintain the image quality at a high level.

  In addition, in the present embodiment, information on the current value adjustment waveform at the start of projection for canceling the luminance variation in each field period for each color component with respect to the LED array 17 as the light source is stored in the program memory 29 in advance. It is assumed that the LED array 17 is controlled by the R driver 22, the G driver 23, and the B driver 24 after being read out at the start of projection and set in the current control unit 25a of the projection light processing unit 25. Then, as the projection operation proceeds, the illuminance sensors 26R, 26G, and 26B periodically measure the deviation of the light amount of each LED, and if a deviation occurs, calculate a current value adjustment waveform for adjusting the deviation, and then project the projection. The current control unit 25a of the light processing unit 25 is reset.

  However, the present invention is not limited to this, and a current value adjustment waveform corresponding to the deviation of the light amount of each LED measured by the illuminance sensors 26R, 26G, and 26B is stored in the program memory 29 in advance and read out as necessary. The LED array 17 may be configured to be set in the current control unit 25a of the projection light processing unit 25 and controlled by the R driver 22, the G driver 23, and the B driver 24.

  By doing in this way, the light quantity can be controlled easily and extremely precisely even in a situation where the light quantity of each of the R, G, and B LED groups constituting the LED array 17 is likely to change due to thermal fluctuation.

  In this regard, in particular, in the above-described embodiment, information on a plurality of patterns of current value adjustment waveforms is stored in advance in the program memory 29, and appropriate current value adjustment waveform information according to the difference between the set contents and the measurement results. Therefore, it is not necessary to perform complicated waveform calculations each time, and the control in the projection light processing unit 25 can be simplified.

  In the present embodiment, when measuring the light amount of the light source, the illuminance from the light source in the micromirror element 16 is measured by the illuminance sensors 26R, 26G, and 26B, so that the light image formed by the micromirror element 16 is measured. By directly measuring the amount of light, the quality of the projected image can be controlled more accurately.

  In the above embodiment, the illuminance sensors 26R, 26G, and 26B have been described as measuring the illuminance from the light source in the micromirror element 16, but the present invention is not limited to this, and for example, the light amount at the output portion of the integrator 19 It is good also as what measures. By doing so, it is not necessary to temporarily form an optical image in which all the R, G, and B pixels have full gradation in the micromirror element 16, and the light quantity can be measured in parallel during a normal projection operation. .

(Second Embodiment)
A second embodiment when the present invention is applied to a data projector apparatus using LEDs as light sources will be described below with reference to the drawings.

  FIG. 5 is a block diagram showing a schematic functional configuration of the electronic circuit provided in the data projector device 10 ′ according to the embodiment. Since it is basically the same as the contents shown in FIG. The description is abbreviate | omitted using the same code | symbol.

  The illuminance sensors 26R, 26G, and 26B shown in FIG. 1 are not provided, and the temperature sensor 41 is provided for the LED array 17 instead. The temperature sensor 41 measures the temperature of the LED array 17 and outputs the measurement result to the projection light processing unit 25.

Next, the operation of the above embodiment will be described.
In the program memory 29, information on current value waveforms for driving the R, G, and B LEDs for each of a plurality of projection color modes is stored in advance as data.

  FIG. 6 shows an example of a projection operation to be executed after the CPU 27 reads out an operation program stored in the program memory 29, develops it, and stores it in the main memory 28 after the power of the data projector apparatus 10 'is turned on. Part.

  Initially, before projecting the input image, various projection color mode names indicating the relationship between the color and brightness of the entire projected image, such as “theater mode” and “presentation mode”, are projected as a list image (steps). S201).

  For this projection, it is determined whether or not an operation for selecting any one of the projected modes has been performed by the operation unit 30 (step S202), and if not operated, the process returns to step S201 again. In this way, the processes in steps S201 and S202 are repeated, and while the list projection of the projection color modes is performed, it waits for one of these modes to be selected.

  When one of the color modes is selected, the operation is determined in step S202, and information on the current value waveform for each of the R, G, B color LEDs corresponding to the selected mode is alternatively selected from the program memory 29. (Step S203), stored in the main memory 28, and set in the current control unit 25a of the projection light processing unit 25 to control the R driver 22, the G driver 23, and the B driver 24 (step S203). Step S204).

  After the setting, the LED array 17 is driven by the R driver 22, the G driver 23, and the B driver 24 according to the current value waveform set in the current control unit 25 a, via the input / output connector unit 11 or the wireless LAN antenna 34. The projection operation of the input image signal is started (step S205).

  At the same time, the CPU 27 causes the timer to set a time for counting in the main memory 28 (step S206). This timer counts a predetermined time T, for example, 30 [minutes] as a measurement interval of thermal fluctuations occurring in each of the R, G, and B LED groups constituting the LED array 17. It is determined whether or not the count value has reached a certain value T as the timer counts (step S207).

  Here, if the count value of the timer has not reached the constant value T, the process returns to step S206 again. Thereafter, the above-described steps S206 and S207 are repeatedly executed while performing the projection operation, thereby waiting for the count value of the timer to reach a constant value T.

  When the count value of the timer reaches a constant value T, it is determined in step S207, and the temperature of the LED array 17 at that time is measured by the temperature sensor 41 (step S208).

  As a result of the measured temperature, the projection light processing unit 25 determines whether or not there is a deviation from the preset temperature of the LED array 17 (step S209).

  If it is determined that there is no deviation between the two temperatures, it is assumed that there is no particular problem, and the count value of the timer is cleared as it is (step S212), and then the process returns to step S206 again.

  If it is determined in step S209 that there is a deviation of a predetermined value or more between the measured temperature and the set temperature, then the deviation of R, G, B constituting the LED array 17 is taken into account. A current value adjustment waveform is calculated so that each LED group has a desired illuminance (step S210).

Thereafter, information corresponding to the calculated current value adjustment waveform is read from the program memory 29 and reset in the current control unit 25a of the projection light processing unit 25 (step S211).
By resetting the current value adjustment waveform to the current control unit 25a of the projection light processing unit 25, the decrease in illuminance due to thermal fluctuation in the LED array 17 is eliminated, and the R, It becomes possible to light each LED group of G and B.

  After the process of step S211, after clearing the count value of the timer in step S212, the process returns to the process from step S206 again.

Thus, according to the present embodiment as described in detail, when measuring the light amount of the light source, the temperature of the LED array 17 is measured by the temperature sensor 41, and the LED array 17 is configured by a deviation from a preset temperature. The decrease in the amount of light emission accompanying the thermal fluctuation of each of the R, G, and B LED groups was estimated.
This makes it possible to control the quality of the projected image to be maintained at a high level while indirectly measuring the change in the light emission amount of the light source with a relatively simple configuration.

  In addition, although the said 1st and 2nd embodiment demonstrated the case where the LED array which has each LED group of R, G, and B3 color was used as a light source, this invention is not restricted to this, It is based on a thermal fluctuation etc. The present invention can be similarly applied to other light sources in which a reduction in the amount of light is a concern, for example, using a semiconductor laser.

  Further, in the above-described embodiment, in each color field, the LEDs of other color components other than the color corresponding to the field are configured to light at the same time while reducing the current value. Is the embodiment that causes the most heat generation between the fields by continuing to be lit in all the fields, so that the effect of suppressing the deterioration of the image quality due to the heat generation of the LED of the present invention can be maximized. It is.

  Therefore, as a matter of course, the effect of the present invention can be exhibited even in other embodiments. For example, when only R, G, and B-LEDs are lit in each of the R, G, and B fields, or when LEDs of colors other than the corresponding colors are lit in pulses in the R, G, and B fields, respectively. The invention can be implemented.

  In addition, this invention is not limited to embodiment mentioned above, In the implementation stage, it can change variously in the range which does not deviate from the summary. Further, the functions executed in the above-described embodiments may be combined as appropriate as possible. The above-described embodiment includes various stages, and various inventions can be extracted by an appropriate combination of a plurality of disclosed constituent elements. For example, even if some constituent requirements are deleted from all the constituent requirements shown in the embodiment, if the effect is obtained, a configuration from which the constituent requirements are deleted can be extracted as an invention.

  DESCRIPTION OF SYMBOLS 10,10 '... Data projector apparatus, 11 ... Input / output connector part, 12 ... Input / output interface (I / F), 13 ... Image conversion part (scaler), 14 ... Video RAM, 15 ... Projection image processing part, 16 ... Micromirror element (SOM), 17 ... LED array, 18 ... housing, 19 ... integrator, 20 ... mirror, 21 ... projection lens unit, 22 ... R driver, 23 ... G driver, 24 ... B driver, 25 ... projection light processing Unit, 25a ... current control unit, 26R, 26G, 26B ... illuminance sensor, 27 ... CPU, 28 ... main memory, 29 ... program memory, 30 ... operation unit, 31 ... voice processing unit, 32 ... wireless LAN interface (I / F), 33 ... Speaker unit, 34 ... Wireless LAN antenna, 41 ... Temperature sensor, SB ... System bus

Claims (12)

A plurality of light emitting elements that respectively emit light of different colors;
Projection means for forming a light image of an image of a plurality of color components for each frame and sequentially projecting the image;
A light source control means for adjusting power supplied to the light emitting element so as to correct a decrease in luminance due to heat generation of the light emitting element, and a selection means for selecting one projection color mode from a plurality of projection color modes;
Storage means for storing in advance power information for correcting a decrease in luminance due to heat generation of the light emitting element,
The storage means stores in advance the power information based on each of the plurality of projection color modes,
The light source control means adjusts the power supplied to the light emitting element based on the projection color mode selected by the selection means.   When the color component of the light image sequentially projected by the projection unit is switched, the light source control unit is configured such that when the set power for a light emitting element that emits light of a certain color component decreases after the switching, The projection apparatus according to claim 1, wherein the power supplied to the light emitting element is gradually reduced after switching.   The projection means emits light of a color component corresponding to the color component of the projected light image, and emits light of a color component other than the light of the corresponding color component of the corresponding color component. The projection apparatus according to claim 1, wherein lighting control is performed so that the light is emitted simultaneously at a lower brightness than the brightness of the light.   The projection apparatus according to claim 1, wherein the power information is a current waveform corresponding to a lapse of time from the light emission start time of the light emitting element. A measuring means for measuring a luminance variation for each color component of light emitted by the light emitting element for each of the plurality of colors;
The storage means stores a plurality of pieces of power information corresponding to luminance fluctuations of light emitted from the light emitting elements for the plurality of colors,
The light source control means reads the corresponding power information from the storage means based on the luminance variation measured by the measuring means, adjusts the power supplied to the light emitting element based on the read power information, and the light emitting element The projection apparatus according to claim 1, wherein the brightness of the projector is adjusted. Further comprising acquisition means for acquiring luminance fluctuations of light emitted by the light emitting element for each of the plurality of colors;
The light source control means calculates power information for adjusting the brightness of the light emitting element for each of the plurality of colors so as to reduce the brightness fluctuation based on the brightness fluctuation acquired by the acquisition means. Item 6. The projection device according to any one of Items 1 to 5.   The projection apparatus according to claim 6, wherein the acquisition unit acquires a luminance variation of the light emitting element by measuring an illuminance of the light emitting element in the projection unit.   The projection apparatus according to claim 6, wherein the acquisition unit acquires a luminance variation of the light emitting element by measuring a temperature of the light emitting element. The acquisition means acquires the luminance fluctuation every predetermined time,
The light source control means calculates the power information to be supplied to the light emitting element each time the luminance fluctuation is acquired,
9. The projection apparatus according to claim 6, wherein the projection unit turns on the light emitting element based on the calculated power information.   10. The projection according to claim 1, wherein the light source control unit adjusts electric power supplied to the light emitting element so that a decrease in luminance of the light emitting element based on the heat generation is offset. 10. apparatus. A projection method of a projection apparatus, comprising: a plurality of light emitting elements that respectively emit light of a plurality of colors; and a projection unit that sequentially forms and projects a light image of an image of a plurality of color components for each frame,
A light source control step of adjusting power supplied to the light emitting element so as to correct a decrease in luminance based on heat generation of the light emitting element;
A selection step of selecting one projection color mode from a plurality of projection color modes;
Storing in advance power information for correcting a decrease in luminance due to heat generation of the light emitting element,
The storing step stores in advance the power information based on each of the plurality of projection color modes,
The light source control step adjusts the power supplied to the light emitting element based on the projection color mode selected in the selection step. A program executed by a computer incorporated in a projection apparatus including a plurality of light emitting elements that respectively emit light of a plurality of colors and a projection unit that sequentially forms and projects a light image of an image of a plurality of color components for each frame. There,
A light source control step of adjusting power supplied to the light emitting element so as to correct a decrease in luminance based on heat generation of the light emitting element;
A selection step of selecting one projection color mode from a plurality of projection color modes;
Storing in advance a storage step of storing power information for correcting a decrease in luminance due to heat generation of the light emitting element,
The storing step stores in advance the power information based on each of the plurality of projection color modes,
The light source control step adjusts the power supplied to the light emitting element based on the projection color mode selected in the selection step.

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