JP2011039322A - Laser projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laser projector, which is inexpensive and capable of improving the luminance and the contrast of an image, while reducing the process load. <P>SOLUTION: An image analysis unit 315 analyzes an image to be formed, in a projection region in a scanning period and specifies a grayscale. A luminance increased image display control unit 316 determines the output luminance of a laser beam in a return section, according to the image analysis result by the image analyzing unit 315. A FPGA (field programmable gate array) 310 allows LDs (laser diodes) 361, 362 to emit laser beams, at the output luminance determined by the luminance increased image display control unit 316, over a prescribed range of the projection region in the return section. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a laser projector that displays an image by scanning light from a laser light source onto a projection surface.

  Conventionally, a laser projector is known as a projector that projects an image input from the outside by laser light. Such a laser projector scans the laser beam in the main scanning direction and the sub-scanning direction on the scanning region, and reverses the sub-scanning direction when the scanning of the laser beam reaches the end of the scanning region. The laser beam scanning is controlled so as to reciprocate between the start end and the end end of the scanning region, and the locus of the laser beam scanned in the main scanning direction is orthogonal to the main scanning direction in the sub-scanning forward path. An image is displayed by forming an image on the projection surface so as to be arranged in the sub-scanning direction. On the other hand, since laser light is not emitted in the sub-scanning return path, the image has low luminance and contrast.

  In order to solve such a problem, for example, there is an optical scanning device in which the same image is drawn on the irradiated object in each of the forward path period and the backward path period in the sub-scanning direction of the galvanometer mirror that scans laser light. Yes (Patent Document 1).

JP 2002-344765 A

  However, in the invention described in Patent Document 1, since the same image is displayed in each of the forward pass period and the return pass period in the sub-scanning direction, it is necessary to complete the operation in one frame (for example, 1/60 second). Therefore, high speed optical scanning is required. For this reason, it is necessary to improve the performance of the apparatus, and there is a problem that the manufacturing cost is increased. In addition, since the same image is displayed twice during one frame, there is a problem that a processing load for displaying the image is increased.

  An object of the present invention is to provide a laser projector capable of improving the brightness and contrast of an image at a low cost and with a small processing load.

In order to solve the above-described problems, the invention described in claim 1 includes a laser light source that emits laser light in accordance with an input image signal;
The laser light from the laser light source is scanned in the main scanning direction and the sub-scanning direction on the scanning area, and when the scanning of the laser light reaches the end of the scanning area, the sub-scanning direction is reversed. A scanning unit that reciprocates the scanning of the laser beam between the start end and the end of the scanning region;
In the laser beam sub-scanning forward path, an image is displayed by causing a laser light source to emit laser light corresponding to the input image signal to a projection area that is an area for displaying an image in the scanning area. In a laser projector comprising a display control unit that performs control,
An image analysis unit for analyzing an image by specifying a gradation of one image formed on the projection region by a laser beam emitted from the laser light source;
Based on the result of the analysis by the image analysis unit, output luminance determining means for determining the output luminance of the laser beam in the sub-scanning return path of the display of the one image;
Luminance increase control means for causing the laser light source to emit laser light over a predetermined range of the projection area in the sub-scanning return path at the output brightness determined by the output brightness determining means;
It is provided with.

The invention according to claim 2 is the laser projector according to claim 1,
The image analysis unit analyzes the one image for each of a plurality of analysis regions,
The output luminance determining means determines an output luminance of laser light for each analysis region,
The brightness increase control means causes the laser light source to emit laser light to the projection area while changing the output brightness of the laser light corresponding to each analysis area based on the determination of the output brightness determination means. It is characterized by.

The invention according to claim 3 is the laser projector according to claim 1 or 2,
The laser light source has a plurality of types of light sources each having a different wavelength,
The output luminance determining means determines the output luminance of the laser beam for each wavelength according to the image analysis result by the image analysis unit.

Invention of Claim 4 is a laser projector as described in any one of Claims 1-3,
The brightness increase control means determines the laser light output time corresponding to the output brightness determined by the output brightness determination means for the laser light source.

According to a fifth aspect of the present invention, there is provided a laser light source that emits laser light in accordance with an input image signal;
The laser light from the laser light source is scanned in the main scanning direction and the sub-scanning direction on the scanning area, and when the scanning of the laser light reaches the end of the scanning area, the sub-scanning direction is reversed. A scanning unit that reciprocates the scanning of the laser beam between the start end and the end of the scanning region;
In the laser beam sub-scanning forward path, an image is displayed by causing a laser light source to emit laser light corresponding to the input image signal to a projection area that is an area for displaying an image in the scanning area. In a laser projector comprising a display control unit that performs control,
An image analysis unit for analyzing an image by specifying a gradation of one image formed on the projection region by a laser beam emitted from the laser light source;
Based on the result of the analysis by the image analysis unit, output luminance determining means for determining the output luminance of the laser beam in the sub-scanning return path of the display of the one image;
Luminance increase control means for causing the laser light source to emit laser light over a predetermined range of the projection area in the sub-scanning return path at the output brightness determined by the output brightness determining means;
With
The image analysis unit analyzes the one image for each of a plurality of analysis regions,
The laser light source has a plurality of types of light sources each having a different wavelength,
The output intensity determination means determines the output luminance of the laser beam for each analysis region and for each wavelength of the laser beam,
The brightness increase control means causes the laser light source to emit laser light to the projection area while changing the output brightness of the laser light corresponding to each analysis area based on the determination of the output brightness determination means, The output time of the laser beam is determined in accordance with the output luminance determined by the output intensity determining means.

  According to the present invention, it is possible to provide a laser projector capable of improving the brightness and contrast of an image at a low cost and with a small processing load.

It is an external view which shows the state in which the projector which concerns on this invention was installed. It is a block diagram which shows the principal part structure of the projector which concerns on this invention. It is a figure explaining the analysis result of the picture concerning the present invention. It is a figure explaining the brightness adjustment of the brightness increase image which concerns on this invention. It is a figure explaining the aspect of the scanning of the laser beam based on this invention. It is explanatory drawing regarding the scanning area in the scanning of the laser beam which concerns on this invention, a projection area, a return area, and a brightness increase projection area. It is a figure which shows the image displayed on the projection area | region which concerns on this invention. It is a figure explaining another aspect of the analysis of the image which concerns on this invention. It is a figure explaining another aspect of the analysis of the image which concerns on this invention. It is a figure explaining another aspect of the analysis of the image which concerns on this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The scope of the invention is not limited to the illustrated example.
In the following description, the left-right direction of the projector 100 in FIG. 1 is the X direction, the front-rear direction is the Y direction, and the height direction is the Z direction.

(Embodiment 1)
For example, as shown in FIG. 1, the projector 100 is installed on a table 120, and laser light emitted toward the screen 130 is projected as a display image 132 </ b> A used for presentation or the like by the projection unit 380. It is a projector.

  Next, for example, as illustrated in FIG. 2, the projector 100 includes a front-end FPGA (Field Programmable Gate Array) 310, a laser emission unit 350, an operation panel 330, a back-end block 340, a ROM 344, a video A RAM 345 and a RAM 346 are included.

The FPGA 310 can be programmed including a timing controller 311, a data controller 312, a bit data conversion unit 313, a data / gradation conversion unit 314, an image analysis unit 315, and a brightness enhancement image display control unit 316. LSI (Large Scale Integration). The FPGA 310 controls the back end block 340 to display an image by emitting laser light to a projection area on the screen 130 based on an image signal temporarily stored in the video RAM 345 as described later. Further, as will be described later, control is performed to emit a laser beam to the projection area on the screen 130 with the output luminance determined by the luminance increase image display control unit 316 serving as output luminance determination means to display the luminance increase image. .
In this way, the FPGA 310 constitutes a luminance increase control unit that causes the laser light source to emit laser light over a predetermined range of the projection area in the sub-scanning return path with the output luminance determined by the output luminance determination unit.

  The timing controller 311 reads out an image signal temporarily stored in the video RAM 345 via the data controller 312 based on a command sent from the CPU 341 included in the back-end block 340. Then, the timing controller 311 acquires a synchronization signal (including a horizontal synchronization signal (HSYNC), a pixel clock signal (PCLK), and the like) included in the image signal. Further, the timing controller 311 generates a command for controlling the timing of laser emission / motor driving of a laser emission unit 350 and an actuator 374, which will be described later, based on the synchronization signal, and the bit data converter 313, drive driver To 373, respectively. Further, the timing controller 311 generates a command for controlling the timing of laser emission / motor driving of the laser emitting unit 350 and the actuator 374 in a return section to be described later, and outputs the command to the brightness enhancement image display control unit 316 and the drive driver. To 373, respectively.

The data controller 312 sends the image signal read from the video RAM 345 to the bit data converter 313.
Based on a command from the timing controller 311, the bit data converter 313 converts the image signal sent from the data controller 312 into data suitable for a format for projection by laser light, and then converts the image signal to data / Send to tone conversion unit 314.

  The data / tone conversion unit 314 displays the data output from the bit data converter 313 and the brightness enhancement image display control unit 316 as three colors of R (Red), G (Green), and B (Blue). Are converted to the tone of the color of the color, and the converted signals are sent to the laser emitting unit 350.

The image analysis unit 315 reads an image signal from the video RAM 345 and performs gradation analysis from the read image signal. Specifically, the image analysis unit 315 reads an image signal of an image (one image) currently being drawn from the video RAM 345, and calculates an average of gradation for each analysis region from the read image signal. Then, the image analysis unit 315 sends data indicating the calculated gradation average for each analysis region to the brightness enhancement image display control unit 316.
Here, a specific example will be described with reference to FIG. 3. The image analysis unit 315 calculates the average of gradation for each of the four vertical analysis areas from the image signal read from the video RAM 345. As a result, as shown in FIG. 3, the average gradation for each region is “255: 180: 128: 77” from the top. Then, the image analysis unit 315 transmits data indicating this to the brightness enhancement image display control unit 316.

The brightness-enhanced image display control unit 316 generates a brightness-enhanced image in which the brightness of the laser beam to be output is determined for each analysis region, based on the data indicating the average gradation for each analysis region input from the image analysis unit 315. Generate. Then, the brightness enhancement image display control unit 316 sends the brightness enhancement image data to the data / gradation conversion unit 314 in response to a command from the timing controller 311. Here, the luminance of the laser beam to be output is, for example, R, G in the uppermost analysis region when the data indicating the average gradation for each analysis region is as shown in FIG. , B are 255, and the second analysis region from the top is 180... For example, when an image having a luminance of 180 is displayed in the projection region corresponding to the second analysis region from the top, as shown in FIG. 4A, the luminance is about 70% of the maximum luminance 255. The laser light is output over the entire projection area in the sub-scanning return path, which will be described later, corresponding to the analysis area. The laser beam may be scanned at the maximum luminance 255 in 70% of the entire projection area corresponding to the analysis area, and the output of the laser beam may be stopped in the remaining 30%. At this time, the region where the output of the laser beam is stopped may not be fixed at one place but may be distributed in several regions. Specifically, for example, as shown in FIG. 4B, the laser beam is output at the maximum luminance 255 until 20% of the entire projection area corresponding to the analysis area is scanned, and then the entire area is scanned. The laser beam output is stopped until 10% of the laser beam is scanned, and this operation is repeated until 90% of the entire projection area is scanned. Then, in the final 10% scan, the laser beam is output at the maximum brightness of 255. Output may be performed, and substantially the same amount of light can be obtained in any manner.
As described above, the luminance-increasing image display control unit constitutes output luminance determining means for determining the output luminance of the laser beam in the sub-scanning return path for displaying one image based on the analysis result by the image analyzing unit.

  The laser emitting unit 350 includes a laser control circuit 351, LDs 361 and 362, a polarization beam splitter 363, a laser detector 370, a lens 371, a scanner mirror 372, a drive driver 373, an actuator 374, and a half mirror 375. And a mirror detector 376 and an adjustment unit 377.

An LD (Laser Diode) 361 is a diode that emits green laser light, and an LD 362 is a diode that emits red and blue laser light, and each is controlled by a laser control circuit 351.
Note that the LD 362 according to the present embodiment is configured integrally with the LD that emits red laser light and the LD that emits blue laser light, but may be configured separately.
As described above, the LDs 361 and 362 constitute a laser light source that emits laser light in accordance with an input image signal.

  The laser control circuit 351 controls the emission amount / timing of the LDs 361 and 362 based on the signal sent from the data / gradation conversion unit 314. Further, the laser control circuit 351 detects the emission state of the laser beam from the output amount of the laser beam detected by a laser detector 370 described later, and adjusts the emission amount of the LDs 361 and 362 based on the emission state. .

  The polarization beam splitter 363 is an optical member that is disposed on the optical path of the laser light emitted from the LD 361 and separates the incident laser light into P-polarized light and S-polarized light. The polarization beam splitter 363 transmits part of the green laser light emitted from the LD 361 toward the lens 371 and reflects the rest toward the laser detector 370. On the other hand, the polarization beam splitter 363 transmits part of the red and blue laser beams emitted from the LD 362 toward the laser detector 370 and reflects the rest toward the lens 371.

The laser detector 370 is, for example, a sensor that detects the output amount of laser light, and is disposed on the optical path of the laser light emitted from the LD 362.
The lens 371 condenses the laser light that has passed through the polarization beam splitter 363.

The scanner mirror 372 is a galvano mirror that can be rotated independently in two axial directions by applying a driving force by an actuator 374 described later, and is incident by adjusting the mirror tilt angle by the rotation. The light reflection direction can be adjusted.
Therefore, for example, as shown in the scanning region formed on the screen 130 in FIG. 5, the laser light can be scanned by sequentially adjusting the reflection direction of the laser light transmitted through the lens 371 by the scanner mirror 372. Become.
Here, the scanning position of the laser beam by the scanner mirror 372 is, as shown in FIG. 5A, in the Y-axis direction (sub-scanning direction) from the upper left corner (starting end) of the scanning area in the sub-scanning forward path. This operation is performed until the movement direction of the X-axis is reversed at the timing when the X-axis direction (main scanning direction) is reached while slowly descending, and reaches the side end, and reaches the lower right corner (terminal) of the scanning area. Is repeated.
In this operation, when the scanning position of the laser light passes over the projection area, the laser light is emitted from the LDs 361 and 362, whereby an image is displayed on the projection area. The image projection for one frame is completed when scanning is completed over the entire projection area.
Thereafter, as shown in FIG. 5B, the scanning position of the laser beam is changed from the sub-scanning forward path to the sub-scanning backward path at the timing when it reaches the lower right corner of the scanning area, and the traveling direction of the Y axis is reversed. This operation is repeated until it rapidly moves up and is displaced in the X-axis direction and reaches (returns to) the upper left corner.
Further, in this operation, when the laser beam scanning position passes over the projection area, the laser light is emitted from the LDs 361 and 362, as described later, so that a brightness increase image is displayed on the projection area.
As described above, the scanner mirror 372 scans the laser light from the laser light source in the main scanning direction and the sub-scanning direction on the scanning region, and performs sub-scanning when the scanning of the laser light reaches the end of the scanning region. A scanning unit that reverses the direction and reciprocates the scanning of the laser beam between the start end and the end of the scanning region is configured.

For example, the drive driver 373 controls the scanning of the laser beam by the scanner mirror 372 by giving a pulse signal corresponding to the drive frequency to the actuator 374 in accordance with a command transmitted from the timing controller 311.
The actuator 374 is, for example, two pulse motors connected to each of the two axes of the scanner mirror 372, and each is driven based on a drive frequency (resonance frequency) instructed by a drive driver 373 described later, and the scanner mirror 372. Is rotated by a predetermined angle.

The half mirror 375 transmits a part of the laser light reflected by the scanner mirror 372 toward the projection unit 380 and reflects the rest toward the mirror detector 376.
The mirror detector 376 is, for example, a tilt angle detector that receives laser light reflected by the half mirror 375 and detects the tilt angle (touch angle) of the scanner mirror 372 in the biaxial direction. The tilt angle detected by the mirror detector 376 is input to the adjustment unit 377 as an analog electric signal.
The adjustment unit 377 includes, for example, an arithmetic unit for arithmetic operation, a comparator, an amplifier for analog signal amplification, an A / D converter, and the like, which are not illustrated, and are input from the mirror detector 376. The analog electrical signal related to the tilt angle of the scanner mirror 372 is adjusted to a desired value through amplification, arithmetic operation, comparison, etc., converted into a digital signal, and transmitted to the CPU 341.
In other words, the resonance frequency of the scanner mirror 372 varies depending on the installation environment (for example, temperature, humidity, atmospheric pressure, etc.), and there is a possibility that the scanning position of the laser beam is displaced. The tilt angle of the mirror 372 is detected and transmitted to the CPU 341 so that the CPU 341 and the timing controller 311 can sequentially adjust the drive frequency by the drive driver 373.

  The operation panel 330 is provided, for example, on the surface or side surface of the casing of the projector 100, and includes a display device (not shown) for displaying operation details, buttons for the user to perform input operations on the projector 100, And a switch (not shown). Then, when an operation by the user is executed, the operation panel 330 transmits a signal corresponding to the operation to the CPU 341.

  The back end block 340 is a back end portion of the projector 100 configured to include a CPU 341, a video I / F 342, and an external I / F 343.

The CPU 341 controls the overall operation of the projector 100 by reading various processing programs stored in the ROM 344, executing the programs, and transmitting output signals to the respective units.
Further, the CPU 341 controls projection of video based on an image signal input to the projector 100 via the video I / F 342 and the external I / F 343 based on a signal transmitted from the operation panel 330. That is, the CPU 341 communicates with the timing controller 311 of the FPGA 310 to control the display of video based on the image signal temporarily stored in the video RAM 345.

  The video I / F 342 is an interface for connecting to an image output device 150 such as a PC (Personal Computer), for example, and inputting an image signal output from the image output device 150.

  The external I / F 343 is an interface for an external storage medium to which a memory card 151 such as a USB (Universal Serial Bus) flash memory or an SD memory card can be mounted, for example, and reads an image signal stored in the memory card 151. Input to the projector 100 is possible.

  The video RAM 345 temporarily stores an image signal input via the video I / F 342 or the external I / F 343. The video RAM 345 is configured such that an image signal is read by the data controller 312 at a timing generated by the timing controller 311 when display control is performed by the FPGA 310.

The ROM 344 is, for example, a non-volatile memory, and includes a storage area for programs executed by the CPU 341 and various data necessary for executing the programs.
The RAM 346 is used as a work area of the CPU 341, for example, and stores processing results generated when various programs are executed by the CPU 341, input data, and the like.

Next, a section in which the laser light scanning position is switched in the laser projector 100 will be described.
As shown in FIG. 6, in the section where the laser beam is scanned by the scanner mirror 372 in the projector 100, the scanner mirror 372 scans the laser beam in the left-right direction (main scanning direction) and is the start of the scanning area. A scanning section (section a) as a scanning forward path in which the scanning position is switched in the vertical direction (sub-scanning direction) from the top row (position “+ θ”) to the bottom row (position “−θ”), which is the end of the scanning region. Among the scanning sections, a projection section (section b) in which laser light is actually emitted to the projection area on the screen 130 and an image is formed, and from the bottom row side, which is the end of the scanning area, to the beginning of the scanning area A return section (section c) as a scanning return path in which the scanning position by the scanner mirror 372 is switched in the vertical direction returning to a certain uppermost row side, and a section in which the projection area is scanned in the return section. There is a brightness increase projection section (section d) that is in between.
Then, by scanning the laser beam in each of the scanning section (section a) and the return section (section c), scanning of the laser light in one frame (1/60 seconds) is performed, and the projection section (section b). The image is displayed in the projection area of the screen 130 by continuously forming a plurality of frames of images by emitting laser light.

  According to the configuration described above, in the projection section (section b in FIG. 6) in one frame (1/60 second), the image shown in FIG. After being displayed, in the brightness increase projection section (section d in FIG. 6), as shown in FIG. 7B, brightness increase images having different brightness corresponding to each analysis area are displayed on the projection area of the screen 130. Is displayed. Thereafter, an image as shown in FIG. 7C is displayed on the projection area of the screen 130 in the projection section of the next frame.

  In the present embodiment, the image analysis unit 315 calculates the average of the gradation for each analysis region, and the luminance increase image display control unit 316 calculates the luminance increase image having the same luminance for R, G, and B. In this case, control is performed so that the brightness is changed corresponding to each analysis region so that the image is displayed on the projection region. However, as shown in FIG. The average of the tone is calculated for each analysis region, and the luminance-increasing image display control unit 316 controls the luminance-increased image to be displayed by changing the luminances of the R, G, and B colors for each analysis region. Good.

In the present embodiment, tone analysis is performed by assigning image signals to a plurality of analysis regions, and brightness-increasing images having different luminances are displayed on the projection region corresponding to each analysis region. As shown in FIG. 9, the average of the gradation of the entire image may be calculated without dividing the region, and the brightness enhancement image may be displayed based on the average.
In the present embodiment, the analysis regions are formed in four vertical areas, but may be formed in a matrix as shown in FIG.

  As described above, according to the present embodiment, the image analysis unit 315 analyzes the image formed in the projection area in the scanning section and specifies the gradation. Then, in accordance with the image analysis result by the image analysis unit 315, the brightness increase image display control unit 316 determines the output luminance of the laser light in the return section. Then, the FPGA 310 causes the LDs 361 and 362 to emit laser light over the predetermined range of the projection area in the return section with the output brightness determined by the brightness increase image display control unit 316. As a result, the brightness increase image displayed in the projection area in the return section causes a so-called backlight effect, and it is not necessary to display a complex image in the return section in order to improve the brightness of the image. It is possible to easily realize it with only software support. Further, since the output luminance of the LDs 361 and 362 in the return section is determined based on the gradation of the image displayed in the scanning section, the contrast can be improved. Therefore, it is possible to improve the luminance and contrast of the image at a low cost and with a small processing load.

  In addition, according to the present embodiment, the image analysis unit 315 analyzes the image for each analysis region, the brightness increase image display control unit 316 determines the output luminance of the laser beam for each analysis region, and the FPGA 310 The laser beam is emitted to the projection region while changing the output luminance of the laser beam corresponding to each analysis region. As a result, since it is possible to display a brightness-enhanced image with different brightness for each of the plurality of regions according to the display mode of the image, the contrast is further improved and the image quality can be improved.

  Further, according to the present embodiment, the LDs 361 and 362 have light sources of three colors having different wavelengths such as red, green, and blue, and the brightness enhancement image display control unit 316 displays the image analysis result by the image analysis unit 315. Accordingly, since the output luminance of the laser beam is determined for each wavelength, the contrast is further improved and the image quality can be improved.

  Further, according to the present embodiment, the FPGA 310 determines the output time of the laser light emitted to the projection region in accordance with the output luminance determined by the luminance increase image display control unit 316 in the LDs 361 and 362. Therefore, it is not necessary to adjust the current for driving the LDs 361 and 362, and the brightness can be easily adjusted.

  In the present embodiment, the image analysis unit 315 analyzes the image based on the displayed image. However, the displayed image (previous frame image) and the next displayed image (rear frame) The image may be analyzed based on the image. Further, the image may be analyzed based on only the next displayed image instead of the currently displayed image.

  In this embodiment, a plurality of analysis areas having a predetermined size are provided, and an image is analyzed for each analysis area. However, the size of the analysis area is not fixed, and the tone of the image is determined. An analysis area may be set. As an analysis region setting method, for example, a difference in gradation between adjacent pixels is determined, and when the difference exceeds a threshold, a boundary is set between the pixels. Then, an area surrounded by the boundary is set as one analysis area. Further, the difference determination may be performed for each of red, green, and blue colors, and the output positions of the red, green, and blue detection lights may be determined based on this.

100 Projector (Laser projector)
130 Screen 310 FPGA (luminance increase control means)
311 Timing controller 312 Data controller 313 Bit data converter 314 Data / gradation conversion unit 315 Image analysis unit 316 Brightness increase image display control unit (output luminance determination means)
340 Backend block 345 Video RAM
350 Laser emitting unit 351 Laser control circuit 361 LD (laser light source)
362 LD (laser light source)
370 Laser Detector 372 Scanner Mirror (Scanning Unit)
373 Drive driver 374 Actuator

Claims (5)

A laser light source that emits laser light in accordance with an input image signal;
The laser light from the laser light source is scanned in the main scanning direction and the sub-scanning direction on the scanning area, and when the scanning of the laser light reaches the end of the scanning area, the sub-scanning direction is reversed. A scanning unit that reciprocates the scanning of the laser beam between the start end and the end of the scanning region;
In the laser beam sub-scanning forward path, an image is displayed by causing a laser light source to emit laser light corresponding to the input image signal to a projection area that is an area for displaying an image in the scanning area. In a laser projector comprising a display control unit that performs control,
An image analysis unit that analyzes an image by specifying a gradation of one image formed on the projection region by laser light emitted from the laser light source;
Based on the result of the analysis by the image analysis unit, output luminance determining means for determining the output luminance of the laser beam in the sub-scanning return path of the display of the one image;
Luminance increase control means for causing the laser light source to emit laser light over a predetermined range of the projection area in the sub-scanning return path at the output brightness determined by the output brightness determining means;
A laser projector comprising: The image analysis unit analyzes the one image for each of a plurality of analysis regions,
The output luminance determining means determines an output luminance of laser light for each analysis region,
The brightness increase control means causes the laser light source to emit laser light to the projection area while changing the output brightness of the laser light corresponding to each analysis area based on the determination of the output brightness determination means. The laser projector according to claim 1. The laser light source has a plurality of types of light sources each having a different wavelength,
3. The laser projector according to claim 1, wherein the output luminance determining unit determines an output luminance of the laser beam for each wavelength according to an image analysis result by the image analysis unit.   4. The laser light source according to claim 1, wherein the brightness increase control unit determines a laser light output time corresponding to the output brightness determined by the output brightness determination unit. A laser projector according to claim 1. A laser light source that emits laser light in accordance with an input image signal;
The laser light from the laser light source is scanned in the main scanning direction and the sub-scanning direction on the scanning area, and when the scanning of the laser light reaches the end of the scanning area, the sub-scanning direction is reversed. A scanning unit that reciprocates the scanning of the laser beam between the start end and the end of the scanning region;
In the laser beam sub-scanning forward path, an image is displayed by causing a laser light source to emit laser light corresponding to the input image signal to a projection area that is an area for displaying an image in the scanning area. In a laser projector comprising a display control unit that performs control,
An image analysis unit for analyzing an image by specifying a gradation of one image formed on the projection region by a laser beam emitted from the laser light source;
Based on the result of the analysis by the image analysis unit, output luminance determining means for determining the output luminance of the laser beam in the sub-scanning return path of the display of the one image;
Luminance increase control means for causing the laser light source to emit laser light over a predetermined range of the projection area in the sub-scanning return path at the output brightness determined by the output brightness determining means;
With
The image analysis unit analyzes the one image for each of a plurality of analysis regions,
The laser light source has a plurality of types of light sources each having a different wavelength,
The output intensity determination means determines the output luminance of the laser beam for each analysis region and for each wavelength of the laser beam,
The brightness increase control means causes the laser light source to emit laser light to the projection area while changing the output brightness of the laser light corresponding to each analysis area based on the determination of the output brightness determination means, A laser projector characterized in that an output time of laser light is determined in accordance with the output luminance determined by the output intensity determining means.

Images