JP2016090635A - Image drawing device and output adjustment method for image drawing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image drawing device capable of suppressing the degradation of drawing quality of an image drawing area by reducing the influence of stray light based on APC bright light.SOLUTION: The image drawing device includes a laser light source control part which performs control for allowing a laser light source part to output characteristic detection laser light for detecting the output value of laser light outputted by the laser light source part, a scanner control part which controls the scanning of a scanner part, so that the scanner part scans the laser light at a predetermined amplitude, and a characteristic detection control part which controls the laser light source control part, so as to output the characteristic detection laser light to the outside of the image drawing area, when the output value of the laser light outputted by the laser light source part is adjusted, controls the scanner control part, so as to perform control for stopping the scanning of the scanner part, in a period when the characteristic detection laser light is outputted, and adjusts the output value of the laser light on the basis of the detection result of the output value of the characteristic detection laser light.SELECTED DRAWING: Figure 8

Description

  The present invention relates to an image drawing apparatus and an output adjustment method for the image drawing apparatus.

  Patent Document 1 discloses a laser projector that displays a desired image on a screen by two-dimensionally scanning laser light output from a semiconductor laser. In general, the I-L characteristic, which is the relationship between the drive current of a laser light source such as a semiconductor laser and the amount of output light, easily changes due to temperature fluctuations of the laser light source itself. Therefore, in Patent Document 1, temperature fluctuation of the laser light source itself is suppressed by appropriately adjusting the drive current of the laser light source while the laser light is shielded by the shielding plate.

JP 2010-139687 A

  By the way, the applicant of the present application outputs a laser beam on a trial basis from a laser light source, and detects an output light amount of the laser light (hereinafter referred to as a characteristic detection laser beam) with a photodiode to obtain an actual light amount for a predetermined drive current. We have developed APC control (Auto Power Control) that periodically adjusts the drive current of the laser light source based on the acquired light quantity. In the APC control, the characteristic detection laser beam is used by using a shielding plate or the like in the same manner as in Patent Document 1 so that the characteristic detection laser beam does not reach a range where a drawn image is presented to a user such as a screen. Shielded.

  Here, the scanning area SA will be described with reference to FIG. The scanning area SA is the above-described two-dimensional scanning area. The scanning area SA has an image drawing area SD and a blanking area SB. The image drawing area SD is a rectangular area in which an image to be displayed on the screen is actually drawn. The blanking area SB is an area where a frame-shaped laser beam surrounding the image drawing area SD is not projected.

  When the image to be rendered is a rectangular shape, the image rendering area SD needs to be rectangular, so that the scanning area SA is desirably rectangular as well. However, as long as the laser light output from the laser light source is reflected and scanned in two stages by the vertical mirror and the horizontal mirror, the scanning area SA does not become a complete rectangle, and as shown in FIG. The long side becomes a distorted shape bulging out in the same direction, and the image drawing area SD is also distorted in the same manner as the scanning area. Therefore, as shown in FIG. 3, by drawing the horizontal line of the image so as to straddle a plurality of horizontal scanning lines, the image drawing area SD is brought close to an ideal rectangle as shown in FIG.

  As described above, in the APC control, the output light amount of the characteristic detection laser beam is detected by the photodiode. Since the detection signal of this photodiode is extremely small, the detection value is appropriately amplified and the detection value is stabilized by using a low-pass filter. For example, a time (for example, 130 microseconds) corresponding to the scanning time for eight horizontal lines is required until the detection value is actually stabilized. FIG. 4 shows a scanning area of APC bright lines in APC control (hereinafter referred to as APC scanning area SP). As shown in FIG. 4, the APC scanning area SP has a width for scanning eight horizontal lines, and has a curved shape like the horizontal scanning lines. On the other hand, since the image drawing area SD is substantially rectangular as described above, the distance between the image drawing area SD and the APC scanning area SP at the upper two corners of the image drawing area SD is smaller than that of the central portion. It is getting smaller. As a result, extremely high accuracy is required for the arrangement of the light shielding plate that does not shield the image drawing area SD but shields the APC scanning area SP, and when the brightness of the image drawn in the image drawing area SD is low. The influence of the stray light from the APC bright line is increased at both ends of the image drawing area SD on the APC scanning area SP side, and the drawing quality of the image drawing area SD is lowered.

  An object of the present invention is to provide a technique for reducing the influence of stray light based on an APC bright line and suppressing a reduction in drawing quality in an image drawing area.

  The present invention includes a laser light source unit that outputs a laser beam, a scanner unit that scans the laser beam output from the laser light source unit in a vertical direction and a horizontal direction, and a scanning region that the scanner unit scans. The laser light output timing and the laser light output value of the laser light source unit are controlled so that a drawn image based on the input image data is generated by scanning of the scanner unit, and the laser light output by the laser light source unit is controlled. A laser light source control unit that controls the laser light source unit to output a characteristic detection laser beam for detecting an output value, and scans the scanner unit so that the scanner unit scans the laser beam with a predetermined amplitude. When the output value of the laser light output from the scanner control unit to be controlled and the laser light source unit is adjusted, the characteristic detection is performed outside the region where the drawing image is generated. The laser light source control unit is controlled to output a laser beam, and the scanner control unit is controlled to stop scanning of the scanner unit during the period during which the characteristic detection laser beam is output. And a characteristic detection control unit that adjusts the output value of the laser beam based on the detection result of the output value of the characteristic detection laser beam.

  Further, the present invention is an image drawing method for generating a drawn image by reflecting the laser beam output from the laser light source unit to the scanner unit, and adjusting the output value of the laser beam output from the laser light source unit In addition, the characteristic detection laser beam is output outside the region where the drawing image is generated, and during the period in which the characteristic detection laser beam is output, scanning by the scanner unit is stopped, and the output value of the characteristic detection laser beam is An output adjustment method for an image drawing apparatus is provided that adjusts an output value of a laser beam based on the detection result.

  ADVANTAGE OF THE INVENTION According to this invention, the influence of the stray light based on an APC bright line can be reduced, and the drawing quality fall of an image drawing area | region can be suppressed.

It is a schematic diagram of a scanning area. It is the figure which drawn the distortion of the scanning area typically. It is a schematic diagram for demonstrating the technique which makes an image drawing area close to a rectangle. It is a schematic diagram for demonstrating the positional relationship of an image drawing area | region and an APC scanning area | region. It is a functional block diagram of an image drawing apparatus. (First embodiment) It is a graph which shows the time change of a vertical scanning angle and a horizontal scanning angle. (First embodiment) 5 is a flowchart illustrating an example of control of an image drawing apparatus in APC processing. (First embodiment) It is a graph which shows typically a time change of a vertical scanning angle and a horizontal scanning angle in APC processing. (First embodiment) It is a figure which shows typically the APC scanning area | region in APC processing. (First embodiment) 5 is a flowchart illustrating an example of control of an image drawing apparatus in APC processing. (Second Embodiment) It is a graph which shows typically a time change of a vertical scanning angle and a horizontal scanning angle in APC processing. (Second Embodiment) It is a figure which shows typically the APC scanning area | region in APC processing. (Second Embodiment)

(First embodiment)
The first embodiment will be described below with reference to the drawings. FIG. 5 shows a functional block diagram of the image drawing apparatus 1 of the first embodiment. The image drawing device 1 is specifically a head-up display device, which is mainly mounted on a vehicle and presents various information as virtual images to a driver who is a user. When the image drawing device 1 is used as a head-up display device, an image intended for route guidance, an image intended for warning, an image based on content reproduction, and an image related to various UIs (User Interfaces) Are presented as virtual images based on the drawn images. These images may be still images or moving images.

  The image drawing apparatus 1 includes a control unit 2, a laser light source unit 3, a scanner unit 4, a DDR memory 5 (Double Data Rate), and a shielding plate 9 as a shielding unit.

  The control unit 2 includes a central processing unit (CPU) (not shown), a read / write free RAM (Random Access Memory), a read-only ROM (Read Only Memory), and the like. Then, when the CPU reads and executes the image drawing program stored in the ROM, the image drawing program uses the hardware such as the CPU as the laser light source control unit 6, the scanner control unit 7, and the characteristic detection control unit 8. Make it work.

  The laser light source unit 3 includes a laser module 10 that outputs laser light, and a laser driver 11 that drives a laser diode 101 provided in the laser module 10. In this embodiment, the laser module 10 includes a red laser diode 101R, a green laser diode 101G, a blue laser diode 101B, a dichroic mirror 102 corresponding to each laser diode 101, and a photodiode 14. The laser beams of the respective colors output from the laser diodes 101 included in the laser module 10 are combined by the dichroic mirror 102 and output to the scanner unit 4. The laser driver 11 drives the laser diode 101 included in the laser module 10 based on the laser drive signal from the control unit 2.

  The dichroic mirror 102R has a characteristic of reflecting almost 100% of the red wavelength light output from the red laser diode 101R. The dichroic mirror 102G has a characteristic of transmitting approximately 100% of the red wavelength light output from the red laser diode 101R and reflecting approximately 100% of the green wavelength light output from the green laser diode 101G. The dichroic mirror 102B has a characteristic of reflecting about 98% and transmitting about 2% of the red wavelength light output from the red laser diode 101R and the green wavelength light output from the green laser diode 101G. Further, the dichroic mirror 102B has a characteristic of transmitting about 98% of the blue wavelength light output from the blue laser diode 101B and reflecting about 2%.

  With the configuration of the dichroic mirror 102 as described above, approximately 98% of the laser light output from each laser diode 101 is reflected by the scanner 12 and approximately 2% of the laser light is incident on the photodiode 14. The photodiode 14 measures the light amount of each laser beam incident as a light amount measuring unit, and outputs the measurement result to the control unit 2. The arrangement of the laser diode 101 and the dichroic mirror 102 is not limited to the arrangement shown in FIG. 5, and the same output may be provided to the scanner unit 4 and the photodiode 14.

  The scanner unit 4 includes a scanner 12 that reflects and scans the laser light output from the laser light source unit 3, a scanner driver 13 that drives the scanner 12, and scanning as a scanning angle detection unit that detects the scanning angle of the scanner 12. And a corner detection unit 15. The scanner 12 includes a vertical mirror 12a that scans laser light in the vertical direction (first scanning direction) and a horizontal mirror 12b that scans laser light in the horizontal direction (second scanning direction). Both the vertical mirror 12a and the horizontal mirror 12b are constituted by MEMS (micro electro mechanical system) mirrors. The scanner driver 13 drives the scanner 12 based on the scanner drive signal from the control unit 2. The scanning angle detector 15 detects the scanning angles of the vertical mirror 12 a and the horizontal mirror 12 b and outputs the detection result to the controller 2.

  When the scanner 12 is composed of a vertical mirror 12a and a horizontal mirror 12b, the vertical mirror 12a generally operates at a scanning angle and an oscillation frequency controlled by the scanner driver 13. Since the horizontal mirror 12b has a high oscillation frequency, the horizontal mirror 12b generally operates at a scanning angle and an oscillation frequency due to resonance. Similarly to the vertical mirror 12a, the horizontal mirror 12b may be configured to operate at a scanning angle and an oscillation frequency controlled by the scanner driver 13.

  Then, based on the input image data input to the control unit 2, a laser beam output from the laser light source unit 3 is scanned by the scanner unit 4, thereby generating a drawn image. In the example of FIG. 5, the laser light scanned by the scanner unit 4 is projected on the screen 16. The screen 16 is generally an intermediate image screen when the image drawing device 1 is used as a head-up display device. Although the structure of the head-up display is not shown, the drawn image projected on the intermediate image screen is projected on a combiner or a windshield of an automobile through reflection by a concave mirror or the like.

  The DDR memory 5 is a frame buffer that temporarily stores input image data input to the control unit 2.

  The shielding plate 9 is a plate that shields laser light. The laser beam shielded by the shielding plate 9 does not reach the projection direction beyond the screen 16. The shielding plate 9 has a shape that shields the characteristic detection laser light without shielding the laser light in the image drawing region SD among the laser light reflected by the scanner unit 4. The shielding plate 9 is formed using a housing of the image drawing apparatus 1 or a housing of a unit including the scanner unit 4 and the laser light source unit 3. Further, when the scanner unit 4 is installed as a module in the image drawing apparatus 1, the shielding plate 9 is installed at a position where laser light is emitted from the module, or from the housing of the image drawing apparatus 1 to the screen 16. The position where the laser beam is emitted may be at the front portion or the rear portion of the screen 16.

  The laser light source control unit 6 is a functional unit that controls the output of the laser diode 101 by outputting a laser drive signal to the laser driver 11. The laser light source controller 6 has a laser drive signal frame buffer 6a. The laser light source controller 6 reads input image data for one frame from the DDR memory 5, and stores the read input image data in the laser drive signal frame buffer 6a as laser drive data. The laser light source controller 6 sequentially outputs the laser drive data stored in the laser drive signal frame buffer 6a to the laser driver 11 as a laser drive signal according to the dot clock. Therefore, the laser light source control unit 6 controls the output timing of the laser light so that a drawn image based on the input image data is generated by scanning of the scanner unit 4 within the scanning range scanned by the scanner unit 4. Further, the laser light source control unit 6 controls driving of the red, blue, and green laser diodes so as to obtain appropriate output values according to the color and luminance of the drawn image based on the input image data.

  The scanner control unit 7 is a functional unit that controls scanning of laser light by the scanner 12 by outputting a scanner drive signal to the scanner driver 13. FIG. 6 shows an example of the vertical scanning angle a of the vertical mirror 12a and the horizontal scanning angle b of the horizontal mirror 12b. As shown in FIG. 6, the vertical scanning angle a is represented by a triangular wave, and the horizontal scanning angle b is represented by a sine wave. The amplitude and scanning center of the vertical scanning angle a are constant, and the amplitude and scanning center of the horizontal scanning angle b are also constant. The scanning frequency of the vertical mirror 12a is 60 Hz, for example. The scanning frequency of the horizontal mirror 12b is higher than the scanning frequency of the vertical mirror 12a, for example, 30 kHz.

  The vertical scanning angle a at the scanning center of the vertical scanning is set as the vertical scanning angle center a0, the vertical scanning angle a at the time of turning up the vertical scanning is set as the turning up scanning angle a1, and the vertical at the time of turning down the vertical scanning. Let the scanning angle a be the downward folding scanning angle a2. FIG. 6 shows a drawing area upper end scanning angle a3 corresponding to the upper end of the image drawing area SD and a drawing area lower end scanning angle a4 corresponding to the lower end of the image drawing area SD. The drawing area upper end scanning angle a3 is a scanning angle between the vertical scanning angle center a0 and the upward folding scanning angle a1. The drawing area lower end scanning angle a4 is a scanning angle between the vertical scanning angle center a0 and the downward folding scanning angle a2. The image drawing area SD corresponds to a scanning angle range between the drawing area upper end scanning angle a3 and the drawing area lower end scanning angle a4. The blanking area SB corresponds to a scanning angle range between the upper folding scanning angle a1 and the drawing area upper end scanning angle a3 and a scanning angle range between the lower folding scanning angle a2 and the drawing area lower end scanning angle a4. . Similarly, the horizontal scanning angle b at the scanning center of the horizontal scanning is set as the horizontal scanning angle center b0.

  The characteristic detection control unit 8 is a functional unit that periodically detects whether an appropriate output light amount is obtained with respect to a predetermined drive current applied to the laser diode 101. For example, the laser diode 101 may not be able to obtain a light amount based on the rated value of the I-L characteristic due to a decrease in ambient temperature. In this case, the color tone of the generated drawn image changes due to different characteristics of the red, blue, and green laser diodes 101. In FIG. 5, the characteristic detection control unit 8 outputs the characteristic detection laser light to each of the red, blue, and green laser diodes 101 constituting the laser diode 101, and measures the light quantity of the characteristic detection laser light from the photodiode 14. Based on the measurement result, the drive current of the laser diode 101 is controlled so that each laser diode 101 outputs an appropriate amount of light. Such processing is referred to as APC processing (Auto Power Control) or APC control. The characteristic detection laser beam is a test laser beam for detecting the output value of the laser beam output from each laser diode 101. The characteristic detection control unit 8 optimizes the control of the laser driver 11 by the laser light source control unit 6 by feeding back the detected output value to the laser light source control unit 6. The frequency with which the characteristic detection control unit 8 executes the APC process is, for example, about once every 12 frames.

  Further, the characteristic detection control unit 8 outputs the characteristic detection laser light outside the image drawing area SD (area where the drawn image is generated) when adjusting the output value of the laser light output from the laser light source section 3. In addition, the laser light source control unit 6 is controlled, and during the period when the characteristic detection laser beam is output, the scanner control unit 7 is controlled to stop the scanning of the scanner unit 4, and the laser beam by the characteristic detection laser beam is controlled. The output value of the laser light is adjusted based on the detection result of the output value.

  Hereinafter, the APC process of the characteristic detection control unit 8 in the operation of the image drawing apparatus 1 will be described in detail with reference to FIG.

  First, the characteristic detection control unit 8 determines whether or not it is time to execute an APC process that is a process of adjusting the output value of the laser beam output from the laser light source unit 3 (S100). When it is determined that it is not time to execute the APC process (S100: NO), the characteristic detection control unit 8 determines whether or not to continue the APC process (S100). On the other hand, if it is determined that it is time to execute the APC process (S100: YES), the characteristic detection control unit 8 performs the characteristic detection laser when scanning outside the image drawing area SD as shown in FIG. The laser light source controller 6 is controlled so as to output light (S110). Further, the characteristic detection control unit 8 controls the scanner control unit 7 to stop horizontal scanning of the scanner unit 4 during the period A during which the characteristic detection laser beam is output (S120). Specifically, the characteristic detection control unit 8 controls the scanner control unit 7 to stop the horizontal scanning of the scanner unit 4 at the center of the scanning range. Note that the horizontal scanning static position of the scanner unit 4 is the center of the scanning range. Next, the characteristic detection control unit 8 detects the light amount of the characteristic detection laser beam using the photodiode 14 (S130). Next, the characteristic detection control unit 8 adjusts the output value of the laser diode 101 based on the detection result of the output value of the characteristic detection laser beam (S140). Then, the characteristic detection control unit 8 controls the scanner control unit 7 to resume horizontal scanning of the scanner unit 4 (S150).

  According to the above control, as shown in FIG. 9, the APC scanning area SP, which is the scanning area of the APC bright lines, becomes a vertically long and narrow area at the center in the horizontal direction. Therefore, the APC scanning area SP is irradiated to a position separated from the image drawing area SD. Thereby, the influence of stray light based on the APC bright line is reduced, and the deterioration of the drawing quality of the image drawing area SD is suppressed. In addition, since a large distance can be secured between the APC scanning area SP and the image drawing area SD, the image drawing area SD is not shielded from light, and so high accuracy is required for the arrangement of the light shielding plate that shields the APC scanning area SP. As a result, the manufacturing cost is reduced. Furthermore, since the APC scanning area SP is a vertically elongated small area, the shielding plate 9 that shields the APC bright lines can be small, which contributes to downsizing of the image drawing apparatus 1.

  Although the first embodiment of the present invention has been described above, the first embodiment has the following features.

(1) The image drawing apparatus 1 scans a laser light source unit 3 that outputs laser light, and reflects the laser light output from the laser light source unit 3 in a vertical direction (vertical direction) and a horizontal direction (horizontal direction). The output timing of the laser beam from the laser light source unit 3 and the laser beam output so that a drawing image based on the input image data is generated by scanning of the scanner unit 4 and the scanning area SA scanned by the scanner unit 4. The laser light source control unit 6 that controls the output value and controls the laser light source unit 3 to output the characteristic detection laser light for detecting the output value of the laser light output from the laser light source unit 3, and the scanner unit 4 is a laser. When adjusting the output value of the laser beam output from the scanner control unit 7 that controls the scanning of the scanner unit 4 and the laser light source unit 3 so as to scan the light with a predetermined amplitude, the image drawing region SD (drawing image) The laser light source control unit 6 is controlled so that the characteristic detection laser beam is output outside the region where the image is generated), and during the period A during which the characteristic detection laser beam is output, the scanner control unit 7 is controlled to control the scanner. And a characteristic detection control unit 8 that performs control to stop scanning of the unit 4 and adjusts the output value of the laser beam based on the detection result of the output value of the characteristic detection laser beam. According to the above configuration, it is possible to suppress the APC bright line from becoming stray light and degrading the drawing quality of the image drawing area SD.

(2) When the characteristic detection control unit 8 adjusts the output value of the laser beam output from the laser light source unit 3, the scanner A controls the scanner control unit 7 during the period A during which the characteristic detection laser beam is output. Control for stopping the horizontal scanning of the unit 4 is performed.

(4) When the characteristic detection control unit 8 adjusts the output value of the laser beam output from the laser light source unit 3, the scanner A controls the scanner control unit 7 during the period A during which the characteristic detection laser beam is output. Control for stopping the horizontal scanning of the unit 4 at the horizontal scanning angle center b0 (the central part of the scanning range) is performed. According to the above configuration, since the horizontal scanning angle center b0 is a static position for horizontal scanning, the horizontal scanning can be stopped with simple control.

(5) An image drawing method for generating a drawn image by reflecting the laser light output from the laser light source unit 3 to the scanner unit 4 is performed when adjusting the output value of the laser light output from the laser light source unit 3. A step (S110) of outputting the characteristic detection laser beam outside the drawing region SD (region where a drawing image is generated), and a step of stopping the scanning by the scanner unit during the period A during which the characteristic detection laser beam is output (S120) And adjusting the output value of the laser beam based on the detection result of the output value of the characteristic detection laser beam (S140). According to the above method, it is possible to prevent the APC bright line from becoming stray light and reducing the drawing quality of the image drawing area SD.

(Second Embodiment)
Next, a second embodiment will be described with reference to FIGS. Hereinafter, the present embodiment will be described with a focus on differences from the first embodiment, and a duplicate description will be omitted.

  In the first embodiment, as shown in FIG. 7, when the APC process is executed, the characteristic detection control unit 8 controls the scanner control unit 7 to scan the scanner during the period A during which the characteristic detection laser beam is output. The horizontal scanning of the unit 4 is stopped (S120). On the other hand, in the present embodiment, as shown in FIGS. 10 and 11, when the APC process is executed, the characteristic detection control unit 8 performs the period A during which the characteristic detection laser light is output during the scanner control unit 7. Is controlled to stop the vertical scanning in addition to the horizontal scanning of the scanner unit 4 (S120).

  Further, after adjusting the output value of the laser diode 101 (S140), the characteristic detection control unit 8 controls the scanner control unit 7 to resume horizontal scanning and vertical scanning of the scanner unit 4 (S150).

  According to the above control, as shown in FIG. 12, the APC scanning area SP, which is the scanning area of the APC bright line, becomes a dotted area at the center in the horizontal direction. Therefore, the APC scanning area SP is irradiated to a position separated from the image drawing area SD. Thereby, the influence of stray light based on the APC bright line is reduced, and the deterioration of the drawing quality of the image drawing area SD is suppressed. In addition, since a large distance can be secured between the APC scanning area SP and the image drawing area SD, the image drawing area SD is not shielded from light, and so high accuracy is required for the arrangement of the light shielding plate that shields the APC scanning area SP. As a result, the manufacturing cost is reduced. Furthermore, since the APC scanning area SP is a small dot-like area, the shielding plate 9 that shields the APC bright lines can be made small, which contributes to the downsizing of the image drawing apparatus 1.

  Although the second embodiment of the present invention has been described above, the first embodiment has the following features.

(3) When the characteristic detection control unit 8 adjusts the output value of the laser beam output from the laser light source unit 3, the scanner A controls the scanner control unit 7 during the period A during which the characteristic detection laser beam is output. In addition to the horizontal scanning of the unit 4, the vertical scanning is stopped. According to the above configuration, since the APC scanning region SP is a small dot-like region, the shielding plate 9 that shields the APC bright lines can be small, which contributes to the downsizing of the image drawing apparatus 1.

  The embodiment of the present invention can be variously modified without departing from the gist thereof. The above embodiments have been described on the assumption that the APC scanning area is set in the blanking area SB above the image drawing area SD. When the APC scanning area is set in the blanking area SB below the image drawing area SD, the horizontal scanning of the scanner unit 4 is performed in the vicinity of both ends of the scanning range while the characteristic detection laser beam is output. The same effect can be obtained by performing the process of stopping. The same applies when the vertical scanning is stopped in addition to the horizontal scanning.

  In summary, the period during which the characteristic detection laser beam is output is based on the positional relationship between the scanning area having a distorted shape as shown in FIG. 4 and the image drawing area SD corrected to be rectangular. The scanning of the scanner unit 4 is stopped at a position where the SP is farthest from the image drawing area SD or in the vicinity thereof.

DESCRIPTION OF SYMBOLS 1 Image drawing apparatus 2 Control part 3 Laser light source part 4 Scanner part 6 Laser light source control part 7 Scanner control part 8 Characteristic detection control part 9 Shielding plate 10 Laser module 11 Laser driver 12 Scanner 12a Vertical mirror 12b Horizontal mirror 13 Scanner driver 14 Photo Diode 15 Scan angle detector 16 Screen
Period A

Claims (5)

A laser light source for outputting laser light;
A scanner unit that reflects and scans the laser beam output from the laser light source unit in the vertical and horizontal directions;
Controlling the laser light output timing and the laser light output value of the laser light source section so that a drawing image based on input image data is generated by scanning of the scanner section in a scanning region scanned by the scanner section; A laser light source controller for controlling the laser light source unit to output a characteristic detection laser beam for detecting an output value of the laser beam output from the laser light source unit;
A scanner control unit that controls scanning of the scanner unit so that the scanner unit scans the laser beam with a predetermined amplitude;
When adjusting the output value of the laser beam output from the laser light source unit, the laser light source control unit is controlled to output the characteristic detection laser beam outside the region where the drawing image is generated, and During the period in which the characteristic detection laser beam is output, the scanner control unit is controlled to stop scanning of the scanner unit, and the output value of the laser beam is based on the detection result of the output value of the characteristic detection laser beam. A characteristic detection control unit for adjusting
An image drawing apparatus comprising: When the characteristic detection control unit adjusts the output value of the laser beam output from the laser light source unit, the characteristic detection control unit controls the scanner control unit during the period during which the characteristic detection laser beam is output. Control to stop horizontal scanning,
The image drawing apparatus according to claim 1. When the characteristic detection control unit adjusts the output value of the laser beam output from the laser light source unit, the characteristic detection control unit controls the scanner control unit during the period during which the characteristic detection laser beam is output. In addition to horizontal scanning, control is performed to stop vertical scanning.
The image drawing apparatus according to claim 1. When the characteristic detection control unit adjusts the output value of the laser beam output from the laser light source unit, the characteristic detection control unit controls the scanner control unit during the period during which the characteristic detection laser beam is output. Control to stop the horizontal scanning at the center of the scanning range,
The image drawing apparatus according to any one of claims 1 to 3. An image drawing method for generating a drawn image by reflecting laser light output from a laser light source unit to a scanner unit,
When adjusting the output value of the laser beam output by the laser light source unit, the characteristic detection laser beam is output outside the region where the drawing image is generated,
During the period when the characteristic detection laser beam is output, the scanning by the scanner unit is stopped,
Adjusting the output value of the laser beam based on the detection result of the output value of the characteristic detection laser beam;
An output adjustment method for an image drawing apparatus.

Images