JP2012068547A - Display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a display device capable of displaying, even when the display start timing is delayed, an image reducing the difficulty of seeing specific information included in the image.SOLUTION: In a head-mounted display, an image is displayed on the retina by a two-dimensional scanning of beam light, which is output corresponding to an image signal in reply to a BD signal. Based on one-side scanning information 320 included in image information 300 of a display target, a one-side scanning range is specified. A one-side scanning signal for displaying the one-side scanning range by one-side scanning, and a both-side scanning signal for displaying an area excluding the one-side scanning range by both-side scanning are generated.

Description

  The present invention relates to a display device that displays an image by scanning a light beam.

  2. Description of the Related Art Conventionally, there has been known a retinal scanning display device that forms an image on a retina by scanning a light beam having an intensity corresponding to an image signal in a two-dimensional direction and projecting it on the retina of the eye. Such a display device includes an optical scanning unit that scans a light beam in a two-dimensional direction by swinging in a sawtooth or sine wave shape. The light beam scanned by the optical scanning unit is detected by a photodetector (hereinafter referred to as a beam detector sensor, abbreviated as a BD sensor) provided at a specific position. Based on the detection timing of the light beam by the BD sensor, a signal (hereinafter referred to as a reference signal) serving as a reference for the timing of emitting the light beam from the light source when drawing is generated by the reference signal generator. At a timing based on the reference signal, a light beam from the light source is emitted.

  In addition to the BD sensor, a display device including an optical sensor that detects a light beam in the forward path and the return path is known. In this display device, the display start timings of the forward path and the backward path are corrected based on the amount of change in the light emission timing when the light beam is detected by the optical sensor. That is, the display start timing shift is corrected by the optical sensor in both the forward path and the backward path. Thereby, the shift | offset | difference of the scanning position of a light beam can be suppressed, and also the shift | offset | difference of the display position of the image by optical scanning can be suppressed (for example, refer patent document 1).

JP 2010-79198 A

  However, even when the display start timing is adjusted based on the amount of change in the light emission timing as described above, the display starts so as to completely match the timing at which the reference signal is generated due to the influence of individual product differences and aging deterioration. It is difficult to adjust the timing. For this reason, there may be a slight shift in display start timing (so-called display start timing delay) with respect to the timing at which the reference signal is generated. Even if the delay time of the light emission timing is small, there is a possibility that the start position and the end position of drawing are shifted in the scanning line, so that a so-called image display position shift occurs.

  In the case of image display that is scanned in one side in the normal main scanning direction, if the light emission timing is delayed, the display position is only slightly shifted and the image itself is not changed. On the other hand, when drawing is performed by reciprocating the light beam in the main scanning direction, if the light emission timing is delayed, drawing is performed on both the horizontal line scanned in the forward direction and the horizontal line scanned in the backward direction. The start position and end position are shifted. As a result, the image shift that occurs at the time of drawing becomes large. For example, if a straight line orthogonal to the scanning direction is drawn, there is a possibility that a large zigzag line is formed. In particular, when displaying specific information such as characters and symbols, there is a concern that a serious problem may occur that identification of information such as characters becomes difficult if image shift occurs.

  The present invention has been made to solve the above-described problem, and even when a display start timing is delayed, it is possible to display so as to reduce the difficulty of visually recognizing specific information included in an image. It is an object to provide a display device that can be used.

  A display device according to an aspect of the present invention includes a reference signal generation unit that generates a reference signal for determining display start timing of an image, and an image signal according to the reference signal generated by the reference signal generation unit And a two-dimensional scanning of the light beam emitted from the light emitting unit in a main scanning direction and a sub-scanning direction substantially orthogonal to the main scanning direction. Optical scanning means for displaying the image on the subject, reciprocating scanning for alternately scanning the forward path and the backward path in the main scanning direction, and one-side scanning for scanning only one of the forward path and the backward path, In the display device that can be selectively executed by the optical scanning unit, a range specifying unit that specifies a one-side scanning range that is a range to be displayed by the one-side scanning based on the image, and the range specifying unit Therefore, a single-side scanning signal generating unit that generates a single-side scanning signal that is the image signal for executing the single-side scanning with respect to the specified single-side scanning range, and a range different from the single-side scanning range in the image. On the other hand, a reciprocating scanning signal generating means for generating a reciprocating scanning signal which is the image signal for executing the reciprocating scanning is provided.

  According to this, in a display device in which a light beam corresponding to the image signal is emitted according to the reference signal and the image is displayed on the subject by two-dimensional scanning of the light beam, one-side scanning is performed based on the display target image. A range is specified. A one-side scanning signal for displaying the one-side scanning range by one-side scanning and a reciprocating scanning signal for displaying a region other than the one-side scanning range by two-way scanning are generated. As a result, even when the display start timing is delayed, at least the specific information included in the one-side scanning range is appropriately displayed, so that it is possible to reduce the difficulty of visually recognizing the specific information included in the image. .

  The display device further includes a delay amount detecting unit that detects a delay amount of the display start timing with respect to the reference signal generated by the reference signal generating unit, and the range specifying unit is detected by the delay amount detecting unit. Alternatively, the one-side scanning range may be specified when the delay amount is outside the predetermined range. In this case, the specific information can be accurately displayed by the one-sided scanning only when the specific information is difficult to visually recognize when the image is displayed by the reciprocating scanning. On the other hand, if specific information is visible even when the image is displayed by reciprocating scanning, the entire image can be displayed by reciprocating scanning with excellent resolution.

  The display device includes range information acquisition means for acquiring range information indicating a position, a shape, and a size of the one-side scanning range in the image, and the range specifying means is acquired by the range information acquisition means. The one-side scanning range may be specified based on the range information. In this case, the one-side scanning range can be accurately specified based on the range information acquired from the outside.

  In the display device, the range information acquisition unit may acquire the range information from image information including the image and the range information. In this case, since the display target image is included in the image information together with the range information regarding the one-side scanning range, the range information corresponding to the display target image can be easily acquired.

  In the display device, the image signal may include the range information in an invalid scanning period other than an effective scanning period for actually displaying an image. In this case, the light emitting means can display the image by distinguishing between the one-side scanning range and the range other than the one-side scanning range by using one image signal, and selectively using the corresponding one-side scanning and reciprocating scanning.

  The display device includes character information specifying means for specifying character information included in the image based on the image information, and the range information acquisition means includes the character information specified by the character information specifying means. The position, shape, and size of the range to be acquired may be acquired as the range information. In this case, since the range information is acquired by analyzing the display target image, it is possible to save time and effort for creating the range information for each image in advance.

  The display device includes one-side scan setting means for setting whether or not to execute the one-side scan, and the range specifying means is set to execute the one-side scan by the one-side scan setting means. In this case, the one-side scanning range may be specified. In this case, since the user can manually switch whether to perform one-side scanning, the convenience of the display device is improved.

  In the display device, when the one-side scanning signal displays the image by the forward scanning, the color information of the pixel displayed in the forward path is the color information of the pixel corresponding to the backward path adjacent to the forward path. On the other hand, when the image is displayed by scanning in the backward path, the color information of the pixel displayed in the backward path may be supplemented with the color information of the pixel corresponding to the forward path adjacent to the backward path. In this case, since the color information of the pixels included in the non-display return path is reflected in the color information of the pixels displayed in the forward path of each adjacent display target, the user can change the information included in the return path based on the display image. Can be estimated or grasped.

FIG. 3 is a diagram showing an external configuration of a head mounted display 200. 3 is a schematic diagram showing an electrical configuration of a head mounted display 200. FIG. 6 is a schematic diagram illustrating a process in which video light 4 is formed on the display unit 40. FIG. 3 is a diagram illustrating a data configuration of image information 300. FIG. It is the example of a screen which displayed image data 310. It is the figure which displayed "2" by reciprocating scanning in the state where the shift | offset | difference of the light emission start timing has not arisen. It is the figure which displayed "2" by reciprocating scanning in the state in which the light emission start timing has shifted. FIG. 6 is a diagram in which “two” is scanned and displayed on one side in a forward path in a state where a deviation in light emission start timing occurs. FIG. 11 is a diagram in which “2” is scanned and displayed on one side in the return path in a state where the emission start timing is shifted. 5 is a flowchart showing main processing of the head mounted display 200. It is an example of a screen displaying image data 310 without applying the present invention. It is a flowchart which shows a specific drawing process (S15). It is a flowchart which shows an even column one side drawing process (S35). It is a flowchart which shows odd-numbered row | line | column one side drawing processing (S37). It is an example of a screen on which image data 310 is displayed by applying the present invention. It is a flowchart which shows the main process of the head mounted display 200 in a 1st modification. It is a flowchart which shows the main process of the head mounted display 200 in a 2nd modification. It is a flowchart which shows N column M line drawing execution (S63) of the even column one side drawing process in a 3rd modification. It is a flowchart which shows N column M line drawing execution (S83) of odd column one side drawing processing in a 3rd modification. It is a figure which shows the example of a display of the image in the 3rd modification.

  Embodiments of the present invention will be described with reference to the drawings. The drawings to be referred to are used to explain technical features that can be adopted by the present invention, and are merely illustrative examples.

  A schematic configuration of the head mounted display 200 will be described with reference to FIG. The head mounted display 200 scans and emits laser light (hereinafter referred to as video light 4) modulated in accordance with an image signal, and directly projects an image on the retina of at least one eye of the user. It is. The head mounted display 200 includes at least the emission device 100, a prism 150, and a head mounting unit 210. The head mounting unit 210 is fixed to the user's head while supporting the output device 100 and the prism 150.

  The emission device 100 emits video light 4 to the prism 150 according to the image signal. The prism 150 is in a fixed position with respect to the emission device 100. The prism 150 reflects the image light 4 emitted from the emission device 100 toward the user's eyes. The prism 150 includes a beam splitter unit (not shown), transmits the external light 5 from the outside, and guides it to the user's eyes. That is, the prism 150 causes the image light 4 incident from the side of the user and the external light 5 from the outside to enter the user's eyes. Thereby, not only an actual field of view but also an image based on the video light 4 emitted from the emission device 100 can be visually recognized.

  The electrical configuration of the head mounted display 200 will be described with reference to FIG. The head mounted display 200 includes a display unit 40, an input unit 41, a communication unit 43, a flash memory 49, a video RAM 44, a font ROM 45, a control unit 46, and a power supply unit 47. The control unit 46 is a part that controls the entire head mounted display 200, and includes a CPU 61, a ROM 62, and a RAM 48. The control unit 46 executes various processes described later when the CPU 61 reads out various programs stored in the ROM 62.

  The display unit 40 is a part that allows the user to visually recognize an image, and includes an image signal processing unit 70, a laser group 72, and a laser driver group 71. The image signal processing unit 70 receives the image signal from the control unit 46, and converts the received image signal into signals necessary for direct projection onto the user's retina. The laser group 72 includes a blue output laser (B laser) 721, a green output laser (G laser) 722, and a red output laser (R laser) 723. The laser group 72 outputs blue, green, and red laser beams. The laser driver group 71 performs control for outputting laser light from the laser group 72. Hereinafter, the B laser 721, the G laser 722, and the R laser 723 are collectively referred to as lasers.

  The display unit 40 includes a vertical scanning mirror 792, a vertical scanning control circuit 791, a horizontal scanning mirror 812, and a horizontal scanning control circuit 811. The vertical scanning mirror 792 performs scanning by reflecting the laser beam output from the laser in the vertical direction (main scanning direction in the present embodiment). The vertical scanning control circuit 791 performs drive control of the vertical scanning mirror 792. The horizontal scanning mirror 812 performs scanning by reflecting the laser beam output from the laser in the horizontal direction (sub-scanning direction of the present embodiment). The horizontal scanning control circuit 811 performs drive control of the horizontal scanning mirror 812.

  The display unit 40 includes a BD sensor 220 and a BD signal detection circuit 230. The BD sensor 220 detects laser light reflected by the vertical scanning mirror 792 (that is, laser light scanned in the main scanning direction). That is, the BD sensor 220 is provided to detect the position of the laser light in the main scanning direction. When the BD sensor 220 detects that the laser beam has reached a predetermined position, the BD signal detection circuit 230 outputs the BD signal to the image signal processing unit 70. The BD signal functions as a signal (that is, a reference signal) serving as a reference for timing of emitting a light beam from the light source when performing drawing, and details thereof will be described later.

  The display unit 40 includes an optical sensor 240 and a delay detection circuit 250. The optical sensor 240 detects the light beam in the forward path and the return path. The delay detection circuit 250 determines the display start timing relative to the timing at which the BD signal is generated based on the amount of change in the light emission timing of the light source (that is, the image display start timing) when the light beam is detected by the optical sensor 240. Detect deviation. In other words, the delay detection circuit 250 detects the delay amount of the display start timing based on the detection result by the optical sensor 240.

  The input unit 41 is a part for the user to input various operations and data, and includes an operation button group 50 and an input control circuit 51. The input control circuit 51 detects that a key of the operation button group 50 has been operated. The input control circuit 51 is electrically connected to the control unit 46 and notifies the control unit 46 of information related to key operations on the operation button group 50.

  The communication unit 43 is a part that transmits and receives image information and the like, and includes a communication module 57 and a communication control circuit 58. The communication module 57 receives an image signal or the like by wireless communication or wired communication with an external device. The communication control circuit 58 controls the communication module 57. The communication control circuit 58 is electrically connected to the control unit 46 and causes the control unit 46 to acquire an image signal.

  The power supply unit 47 includes a battery 59 and a charge control circuit 60. The battery 59 is a rechargeable battery that serves as a power source for driving the head mounted display 200. The charge control circuit 60 supplies the power of the battery 59 to the head mounted display 200 or charges the battery 59 with the power supplied from a charging adapter (not shown).

  The flash memory 49, the video RAM 44, and the font ROM 45 are electrically connected to the control unit 46 via buses. The flash memory 49 stores various setting values of functions used in the head mounted display 200, image information 300 (see FIG. 4), and the like. The image information 300 includes header information described later in addition to the image data displayed on the display unit 40. In the video RAM 44, image data included in the image information 300 is developed. The font ROM 45 stores font data of text to be displayed on the display unit 40.

  With reference to FIG. 3, an outline of a process in which the image light 4 is formed on the display unit 40 will be described. The display unit 40 includes a light source unit 65, a collimating optical system 77, a horizontal scanning system 81, a first relay optical system 80, a vertical scanning system 79, and a second relay optical system 82. The light source unit 65 includes an image signal processing unit 70, a laser driver group 71, a laser group 72, a collimating optical system 73, a dichroic mirror group 74, a coupling optical system 75, and a BD signal detection circuit 230. The horizontal scanning system 81 includes a horizontal scanning control circuit 811 and a horizontal scanning mirror 812. The vertical scanning system 79 includes a vertical scanning control circuit 791 and a vertical scanning mirror 792.

  The image signal processing unit 70 receives an image signal of image data developed in, for example, the video RAM 44 in order to project desired information on the retina via the control unit 46. The image signal processing unit 70 has a luminance signal 66 (B luminance signal 661, G luminance signal 662, R luminance signal 663), vertical synchronization signal 68, and horizontal for each pixel constituting an image to be projected on the user's retina. A synchronization signal 67 is generated. The B luminance signal 661, the G luminance signal 662, and the R luminance signal 663 are signals for outputting blue, green, and red laser beams, respectively.

  The image signal processing unit 70 converts the generated luminance signal 66 (B luminance signal 661, G luminance signal 662, R luminance signal 663) into a laser driver group 71 (B laser driver 711, G laser driver 712, R laser driver 713). To enter each. However, the image signal processing unit 70 waits for a predetermined time after the BD signal is input from the BD signal detection circuit 230 and the laser beam reaches a predetermined position, and then the luminance signal 66 is transmitted to the laser driver group. To 71. As described above, the BD signal serves as a reference for the timing of emitting the light beam from the light source when performing drawing (that is, the display start timing).

  Thereby, the display start timing is determined for each scanning line (that is, one scanning line in the main scanning direction), and image display is started at the determined display start timing. As a result, the correspondence between the image signal and the laser scanning position is ensured. Furthermore, in the present embodiment, a drawing process is executed in accordance with the delay amount of the display start timing detected by the delay detection circuit 250. Details will be described later.

  The laser driver group 71 causes the laser group 72 to emit intensity-modulated laser light based on the input luminance signal 66 (B luminance signal 661, G luminance signal 662, and R luminance signal 663). Specifically, the B laser driver 711, the G laser driver 712, and the R laser driver 713 are based on the input B luminance signal 661, G luminance signal 662, and R luminance signal 663, respectively, Each drive signal is output to the R laser 723. Based on these drive signals, the B laser 721, the G laser 722, and the R laser 723 each generate intensity-modulated laser light.

  The light source unit 65 is provided with a collimating optical system 73 (731 to 733), a dichroic mirror group 74 (741 to 743), and a coupling optical system 75. The laser light generated by the laser group 72 is output to the collimating optical system 73. The collimating optical system 73 (731 to 733) collimates the three colors (blue, green, and red) of laser light emitted from the laser group 72 under the control of the laser driver group 71 into parallel light. The laser light collimated by the collimating optical system 73 is incident on the dichroic mirror group 74. In the dichroic mirror group 74 (741 to 743), the three colors of laser light collimated by the collimating optical system 73 are combined into one laser light. The laser light combined by the dichroic mirror group 74 is guided to the optical fiber 76 by the coupling optical system 75.

  The laser light transmitted through the optical fiber 76 is guided from the optical fiber 76 to the collimating optical system 77 and then emitted to the vertical scanning system 79. The vertical scanning system 79 of this embodiment is an optical system for scanning the laser beam in the vertical direction (main scanning direction) for each scanning line of an image to be displayed. The vertical scanning system 79 is designed to scan the laser beam at a higher speed (that is, at a higher frequency) than the horizontal scanning system 81. The laser beam emitted to the vertical scanning system 79 is applied to the deflection surface 793 of the vertical scanning mirror 792.

  The image signal processing unit 70 inputs the generated vertical synchronization signal 68 to the vertical scanning control circuit 791 of the vertical scanning system 79. The vertical scanning control circuit 791 reflects the laser beam in the vertical direction on the deflection surface 793 while reciprocatingly vibrating the vertical scanning mirror 792 in synchronization with the input vertical synchronization signal 68. As a result, the laser light applied to the deflection surface 793 is scanned in the vertical direction in synchronization with the vertical synchronization signal 68.

  The vertically scanned laser light is emitted to the horizontal scanning system 81 via the first relay optical system 80. The horizontal scanning system 81 of this embodiment is an optical system for scanning the laser beam in the horizontal direction (sub-scanning direction) from the first scanning line to the last scanning line for each frame of an image to be displayed. . The laser beam emitted to the horizontal scanning system 81 is applied to the deflection surface 813 of the horizontal scanning mirror 812.

  The image signal processing unit 70 inputs the generated horizontal synchronization signal 67 to the horizontal scanning control circuit 811 of the horizontal scanning system 81. The horizontal scanning control circuit 811 reflects the laser beam in the horizontal direction on the deflection surface 813 while reciprocatingly vibrating the horizontal scanning mirror 812 in synchronization with the input horizontal synchronization signal 67. As a result, the laser light applied to the deflection surface 813 is scanned in the horizontal direction in synchronization with the horizontal synchronization signal 67.

  Laser light (image light 4 shown in FIG. 1) that has been two-dimensionally scanned by the vertical scanning system 79 and the horizontal scanning system 81 passes through the second relay optical system 82 and the second relay optical system 82 and the user's pupil 90. It is emitted toward the prism 150 arranged between the two. The image light 4 guided by the second relay optical system 82 is totally reflected by the prism 150 and guided to the pupil 90 of the user. Thereby, an image based on the image data developed in the video RAM 44 is formed on the retina of the user. That is, the user can recognize an image by laser light that is two-dimensionally scanned and projected onto the retina.

  The data configuration of the image information 300 will be described with reference to FIGS. 4 and 5. As shown in FIG. 4, the image information 300 includes a body including image data 310 (see FIG. 5) and a header including various information related to the image data 310. One-side scanning information 320 is included in the header of the image information 300. The one-side scanning information 320 is information indicating a region (hereinafter referred to as one-side scanning range) in the image data 310 where an image is formed by one-side scanning. Specifically, the one-side scanning information 320 indicates the number of one-side scanning ranges (one-side scanning range number) included in the image data 310. Furthermore, block information (first block, second block,...) Corresponding to the number of one-side scanning ranges is included. Each block information indicates the position and size of the one-side scanning range in the image data 310.

  As shown in FIG. 5, the image data 310 of the present embodiment is an adjustment screen for allowing the user to manually correct the image shift. The image data 310 includes two pieces of one-side scanning information 320 (first block 311 and second block 312). The first block 311 is an area for displaying an image adjustment method to the user. The second block 312 is an area for displaying a button for the user to perform image adjustment. Further, the image data 310 includes a predetermined area 313 in which an image adjustment line is displayed in a display area other than the one-side scanning information 320.

  In the example of the image information 300 illustrated in FIG. 4, “2” is set as the number of one-side scanning ranges corresponding to the image data 310 described above. A coordinate position indicating the shape and size of the first block 311 and a coordinate position indicating the shape and size of the second block 312 are set. Since the one-side scanning range of the present embodiment is a rectangular region extending in the Y direction (main scanning direction) and the X direction (sub-scanning direction), the coordinate positions of the two points located on the diagonal (upper left X coordinate, The position and size of the one-side scanning range are indicated by upper left Y coordinate, lower right X coordinate, lower right Y coordinate).

  With reference to FIGS. 6 to 9, the characteristics of the one-side scanning and the reciprocating scanning will be described. 6 to 8 exemplify a case where “two” is displayed with a total of 100 pixels configured by 10 pixels in the column direction (main scanning direction) and 10 pixels in the row direction (sub-scanning direction).

  In the example shown in FIGS. 6 and 7, the columns constituting the image are reciprocated in ascending order so that the path for scanning each row in ascending order (forward path) and the path for scanning each row in descending order (return path) are alternated. Scanning. That is, “2” is displayed by scanning the forward path when scanning an odd-numbered column and scanning the backward path when scanning an even-numbered column. If there is no shift in the display start timing in both the forward path and the return path, there is no shift in the scanning position of the light beam, so that “2” is displayed accurately as shown in FIG. On the other hand, when a display start timing shift occurs in either the forward path or the return path, a shift in the scanning position of the light beam also occurs. For example, when the display start timing in the backward path is delayed by 2 pixels, the scanning position of the backward path moves along the main scanning direction by 2 pixels. As a result, as shown in FIG. 7, “2” is blurred in the main scanning direction, making it difficult to see.

  In the example shown in FIG. 8, only odd-numbered columns are scanned on one side in ascending order. That is, “2” is displayed by scanning only the odd-numbered columns in the forward direction. In this case, since the image is not displayed in the even-numbered columns, the resolution of the entire image is lowered. However, even when a display start timing shift occurs on the return path as described above, “2” is accurately displayed without being affected by this, so that the visibility of the image can be ensured.

  In the example shown in FIG. 9, only the even-numbered columns are scanned on one side in ascending order. That is, “2” is displayed by scanning only the even-numbered columns in the forward direction. In this case, since the image is not displayed in the odd-numbered columns, the resolution of the entire image is lowered. However, even when the display start timing is shifted in the return path as described above, the same number of pixels are shifted in the same direction in the even-numbered columns, so that “2” is accurately displayed. That is, according to the one-side scanning, it is possible to ensure the visibility of the image even when the display start timing is shifted in either the forward path or the backward path.

  With reference to FIGS. 10-15, the main process performed with the head mounted display 200 is demonstrated. This process is executed by the CPU 61 based on a program stored in the ROM 62 when the power of the head mounted display 200 is turned on.

  As shown in FIG. 10, in the main process of the head mounted display 200, it is determined whether or not image information is input (S1). For example, the user designates image information to be displayed on the head mounted display 200 from the flash memory 49 using the operation button group 50. Then, the designated image information (detailed image data 310 described later) is developed in the video RAM 44, and it is determined that image information has been input (S1: YES). If there is no input of image information (S1: NO), a standby state is entered in step S1.

  When image information is input (S1: YES), the delay amount of the display start timing detected by the delay detection circuit 250 is acquired via the image signal processing unit 70 (S3). In step S3, for example, the delay amount of the display start timing may be acquired by drawing the test pattern by several reciprocating scans. Then, it is determined whether or not the acquired delay amount is larger than a predetermined value (S5). When the delay amount is equal to or smaller than the predetermined value (S5: NO), it is estimated that even if the drawing is performed by reciprocating scanning, the image blur is small and the readable image quality can be secured.

  Therefore, the display information input in step S1 is drawn by the above-described reciprocating scanning (S7). Specifically, an image signal (reciprocating scanning signal) for displaying an image by reciprocating scanning is generated for each pixel constituting the image data 310 developed in the RAM 44 and input to the image signal processing unit 70. In this embodiment, based on the image data 310 included in the image information 300, an adjustment screen as shown in FIG.

  On the other hand, when the delay amount is larger than the predetermined value (S5: YES), it is estimated that the image quality is not ensured because the image blurs greatly when drawing by reciprocating scanning. Specifically, when an image is formed by reciprocating scanning based on the image data 310 included in the image information 300, the image may be blurred in the main scanning direction (vertical direction in FIG. 11) as shown in FIG. Therefore, in this case, the header of the display information input in step S1 is analyzed (S9). Single-sided scanning information is acquired from the analyzed header (S11). Based on the acquired one-side scanning information, the one-side scanning range included in the image is specified (S13).

  In the present embodiment, the one-side scanning information 320 illustrated in FIG. 4 is acquired from the header of the image information 300. Based on the one-side scanning information 320, the first block 311 and the second block 312 shown in FIG. 5 are specified as the one-side scanning range. After execution of step S13, the display information input in step S1 is drawn by a specific drawing process (S15) described later. After execution of step S7 or step S15, the process returns to step S1.

  As shown in FIG. 12, in the specific drawing process (S15), first, 1 is assigned to each of the two variables N and M stored in the RAM 62 (S31). Then, it is determined whether or not the one-side scanning target is an even-numbered column (S33). Specifically, it is preset in the predetermined storage area of the flash memory 49 which one of “even-numbered columns” and “odd-numbered columns” is to be scanned on one side when the one-side scanning is executed. When “even column” is set in the predetermined storage area of the flash memory 49, it is determined that the one-side scanning target is an even column (step S33: YES). In this case, an even-numbered column one-side drawing process described later is executed (S35).

  On the other hand, when “odd number column” is set in the predetermined storage area of the flash memory 49, it is determined that the one-side scan target is an odd number column (step S33: NO). In this case, an odd-numbered column one-side drawing process described later is executed (S37). After execution of step S35 or step S37, the process returns to the main process (see FIG. 10).

  As shown in FIG. 13, in the even-column one-side drawing process (S35), it is first determined whether or not the variable N is an even number (S51). When the variable N is an even number (S51: YES), drawing is executed for all the rows included in the N columns to be drawn (S53). Specifically, an image signal (one-side scanning signal) for displaying an image by forward scanning is generated for each pixel constituting the N columns of the image data 310 developed in the RAM 44 and is sent to the image signal processing unit 70. input. As a result, the even-numbered columns to be drawn are all drawn in the forward path regardless of whether or not the one-side scanning range is displayed.

  After execution of step S53, it is determined whether or not the N column is the last column in the image (S55). When the N column is not the final column (S55: NO), 1 is added to the variable N, and 1 is substituted into the variable M (S57). That is, the variable N is incremented and the variable M is reset to 1. After execution of step S57, the process returns to step S51, and the same determination is made for the next row in the image.

  Returning to step S51, if the variable N is not an even number (S51: NO), the N columns to be drawn are odd columns. In this case, it is determined whether or not the pixels in N columns and M rows are within the one-side scanning range (S59). In step S59, based on the one-side scanning range specified in step S13, it is determined whether or not N columns and M rows to be drawn are included in the one-side scanning range. When the pixels in N columns and M rows are within the one-side scanning range (S59: YES), the drawing of N columns and M rows is stopped (S61). That is, nothing is drawn in the odd-numbered pixels included in the one-side scanning range in the image.

  On the other hand, when the pixels in N columns and M rows are outside the one-side scanning range (S59: NO), drawing in N columns and M rows is executed (S63). Specifically, an image signal (one-side scanning signal) for displaying an image in the backward scan is generated based on the pixels constituting N columns and M rows of the image data 310 developed in the RAM 44, and image signal processing is performed. Input to the unit 70. As a result, the pixels in the odd-numbered columns that are not included in the one-side scanning range in the image are drawn on the return path as usual. After execution of step S61 or step S63, it is determined whether or not the M row is the last row in the N columns (S65). If the M line is not the last line (S65: NO), 1 is added to the variable M (S57). That is, the variable M is incremented, and the process returns to step S59. Thereby, the above process is repeated until step S61 or S63 is executed for all the rows in the N columns.

  If the M line is the last line (S65: YES), the process proceeds to step S55. As a result, the above-described processing is repeated until S53 is executed for all even-numbered columns in the image and S59 to S65 are executed for all odd-numbered columns. When the process is executed up to the final column (S55: YES), the process returns to the specific drawing process (see FIG. 12).

  As shown in FIG. 14, in the odd-numbered column one-side drawing process (S37), the same processing as the even-numbered column one-side drawing process (FIG. 13) is executed, but the target column for one-side scanning is different. That is, it is first determined whether or not the variable N is an odd number (S71). When the variable N is an odd number (S71: YES), drawing is executed for all the rows included in the N columns to be drawn (S73). After execution of step S73, it is determined whether or not the N column is the last column in the image (S75). When the N column is not the final column (S75: NO), 1 is added to the variable N, and 1 is substituted into the variable M (S77). That is, the variable N is incremented and the variable M is reset to 1. After execution of step S77, the process returns to step S71, and the same determination is made for the next row in the image.

  Returning to step S71, if the variable N is not an odd number (S71: NO), the N columns to be drawn are even columns. In this case, it is determined whether or not the pixels in N columns and M rows are within the one-side scanning range (S79). When the pixels in N columns and M rows are within the one-side scanning range (S79: YES), drawing in N columns and M rows is stopped (S81). On the other hand, when the pixels in N columns and M rows are outside the one-side scanning range (S79: NO), drawing in N columns and M rows is executed (S83). After execution of step S81 or step S83, it is determined whether or not the M row is the last row in the N columns (S85). If the M line is not the last line (S85: NO), 1 is added to the variable M (S87). That is, the variable M is incremented, and the process returns to step S79. If the M line is the last line (S85: YES), the process proceeds to step S75. When the process is executed up to the final column (S75: YES), the process returns to the specific drawing process (see FIG. 12).

  When the one-side scanning range is included in the image to be displayed by the above processing, the one-side scanning range is displayed by one-side scanning, and the other part is displayed by reciprocating scanning. As a result, as shown in FIG. 15, in the image data 310, the first block 311 and the second block 312 are displayed by one-sided scanning, so that the user can reliably display characters and symbols in the blocks 311 and 312. Visible. Further, since the portions other than the first block 311 and the second block 312 are displayed by reciprocating scanning, the graphic displayed in the predetermined area 313 is displayed in a state of being shaken in the main scanning direction.

  Therefore, in the example of the adjustment screen shown in FIG. 15, the user can know the image adjustment method by reading the characters displayed in the first block 311. The user can manually adjust the blurring of the graphic displayed in the predetermined area 313 using the adjustment button displayed in the second block 312. In the head mounted display 200, by correcting the display start timing in accordance with the user's image adjustment, it is possible to suppress the occurrence of image shift and blurring thereafter.

  As described above, according to the head mounted display 200 of the present embodiment, the beam light corresponding to the image signal is emitted according to the BD signal, and the beam light is scanned two-dimensionally so that the image is formed on the retina. Is displayed. A one-side scanning range is specified based on one-side scanning information included in image information to be displayed. A one-side scanning signal for displaying the one-side scanning range by one-side scanning and a reciprocating scanning signal for displaying a region other than the one-side scanning range by two-way scanning are generated. As a result, even when the display start timing is delayed, at least the character information included in the one-side scanning range is appropriately displayed, so that it is possible to reduce the difficulty of visually recognizing the character information included in the image. .

  Further, when the delay amount of the display start timing is outside the predetermined range, the one-side scanning range is specified and the specific drawing process (FIG. 12) is executed. Therefore, character information and the like can be accurately displayed by one-sided scanning only when specific information is difficult to visually recognize when the image is displayed by reciprocating scanning. On the other hand, when the character information or the like can be visually recognized even when the image is displayed by reciprocating scanning, the entire image can be displayed by reciprocating scanning with excellent resolution. Furthermore, since the image information 300 of the present embodiment includes the image data 310 and the one-side scanning information 320, the one-side scanning information 320 corresponding to the image data 310 to be displayed can be easily acquired.

  In the above embodiment, the head mounted display 200 corresponds to the “display device” of the present invention. The BD signal detection circuit 230 corresponds to the “reference signal generation unit” of the present invention. The image signal processing unit 70 corresponds to the “light emitting means” of the present invention. The vertical scanning system 79 and the horizontal scanning system 81 correspond to the “optical scanning unit” of the present invention. The CPU 61 that executes step S13 corresponds to the “range specifying means” of the present invention. The CPU 61 that executes steps S53, S63, S73, and S83 corresponds to the “one-side scanning signal generating unit” of the present invention. The CPU 61 that executes step S7 corresponds to the “reciprocating scanning signal generating means” of the present invention. The delay detection circuit 250 corresponds to the “delay amount detection means” of the present invention.

  In addition, this invention is not limited to the said embodiment, The change in the range which does not change the summary of invention is possible. For example, in the above-described embodiment, the head-mounted display 200 of the retinal scanning display is illustrated, but the present invention can be applied to any display device that displays an image by two-dimensionally scanning a light beam.

  In the above embodiment, the single-side scanning information is acquired from the image information, but the single-side scanning information may be acquired by other methods. Specifically, in the main process of the head mounted display 200 shown in FIG. 16, first, processes similar to the above-described steps S1 to S7 are executed (S101 to S107). On the other hand, when the delay amount is larger than the predetermined value (S105: YES), it is determined whether or not one-side scanning information is input (S109). For example, when the user inputs the one-side scanning information 320 using the operation button group 50, it is determined that the one-side scanning information is input (S109: YES). In this case, the input one-side scanning information is acquired (S111), the one-side scanning range is specified based on the acquired one-side scanning information (S113), and the specific drawing process similar to step S15 is executed (S115). ). On the other hand, when no one-side scanning information is input (S109: NO), drawing is performed by reciprocating scanning (S107).

  Thereby, even when the one-side scanning information is not included in the image information, it is possible to reduce difficulty in visually recognizing the character information included in the image as in the above embodiment. In this modification, the CPU 61 that executes step S111 corresponds to the “range information acquisition unit” of the present invention.

  In the main process of the head mounted display 200 shown in FIG. 17, first, processes similar to the above-described steps S1 to S7 are executed (S151 to S157). On the other hand, when the delay amount is larger than the predetermined value (S105: YES), the characters included in the image are analyzed (S159). As a character analysis method based on an image, a known pattern matching method, structure analysis method, or the like may be used. The range including the character specified in step S159 (that is, the character recognition range) is specified as the one-side scanning range (S161). Then, one-side scanning information regarding the specified one-side scanning range is acquired (S163), and a specific drawing process similar to step S15 is executed (S165).

  Thereby, since the one-side scanning information is acquired by analyzing the display target image, it is possible to save time and effort for creating one-side scanning information for each image in advance. The CPU 61 executing step S159 corresponds to the “character information specifying unit” of the present invention. The CPU 61 that executes step S163 corresponds to the “range information acquisition unit” of the present invention.

  In the above embodiment, the specific drawing process is executed when the delay amount is larger than the predetermined value. However, the specific drawing process (S15) may be executed based on other criteria. For example, the user may be able to freely set whether or not to execute the specific drawing process (S15) using the operation button group 50. In this case, it is determined whether or not the setting for executing the specific drawing process (S15) is made in step S5, and if the specific drawing process (S15) or the drawing (S7) is executed by reciprocating scanning according to the setting contents. Good. Thereby, since the user can switch whether to perform one-side scanning manually, the convenience of the head mounted display 200 is improved. In this modification, the operation button group 50 corresponds to “one-sided scanning setting means” of the present invention.

  In the above embodiment, an image signal (reciprocating scanning signal, one-side scanning signal) is generated and output in pixel units of the image. However, even if one continuous image signal for displaying the entire image is generated and output. Good. In this case, the image signal only needs to include one-side scanning information in an invalid scanning period other than the effective scanning period in which image display is actually performed. As a result, the image signal processing unit 70 distinguishes between the one-side scanning range and the range other than the one-side scanning range based on one image signal, and displays the image by properly using the corresponding one-side scanning and reciprocating scanning. Can do.

  Further, in the above embodiment, the forward or backward pixels in the one-side scanning range are not displayed, but the color information of adjacent pixels may be supplemented with the color information of the non-displayed pixels. Specifically, in FIG. 13 showing the even-column one-side drawing process (S35) shown in FIG. 12, the N-column M-row drawing execution (S63) may be executed according to the flowchart shown in FIG. Further, in FIG. 14 showing the odd-numbered column one-side drawing process (S37) shown in FIG. 12, the N-column M-row drawing execution (S83) may be executed according to the flowchart shown in FIG.

  As shown in FIG. 18, in drawing execution of N columns and M rows (S63) in the even-column single-side drawing process, it is first determined whether or not (N-1) columns exist (S201). That is, it is determined whether or not a previous column exists in the current display target column. When there are (N-1) columns (S201: YES), pixel information of N columns and M rows and (N-1) columns and M rows is acquired (S203). That is, the color information of N columns and M rows that are display target pixels and the color information of (N-1) columns and M rows that are adjacent pixels of the previous column are acquired.

  An intermediate value between the two pieces of pixel information acquired in step S203 is calculated (S205), and the pixel information of N columns and M rows is overwritten with the calculated intermediate value (S207). As a result, the color information of the N columns and M rows that are the pixels to be displayed is updated to the intermediate color information. After execution of step S207, or when there is no (N-1) column (S201: NO), drawing is executed based on the pixel information of N columns and M rows (S209). Thereby, the color information of the pixels in the odd-numbered columns that are not displayed is reflected as the color information of the pixels in the even-numbered columns that are the next columns of the odd-numbered columns. Thereafter, the processing returns to the even-column one-side drawing processing (FIG. 13).

  As shown in FIG. 19, in drawing execution of N columns and M rows in the odd column one-side drawing processing (S83), it is first determined whether or not there are (N + 1) columns (S251). That is, it is determined whether or not the next column exists in the current display target column. When there are (N + 1) columns (S251: YES), pixel information of N columns and M rows and (N + 1) columns and M rows is acquired (S253). That is, color information of N columns and M rows that are display target pixels and color information of (N + 1) columns and M rows that are adjacent pixels of the next column are acquired.

  An intermediate value between the two pieces of pixel information acquired in step S253 is calculated (S255), and the pixel information of N columns and M rows is overwritten with the calculated intermediate value (S257). As a result, the color information of the N columns and M rows that are the pixels to be displayed is updated to the intermediate color information. After execution of step S257, or when there is no (N + 1) column (S251: NO), drawing is executed based on the pixel information of N columns and M rows (S259). Thereby, the color information of the pixels in the even-numbered columns that are not displayed is reflected as the color information of the pixels in the odd-numbered columns corresponding to the previous column of each even-numbered column. Thereafter, the process returns to the odd-numbered column one-side drawing process (FIG. 14).

  FIG. 20 illustrates a case where odd-numbered columns are scanned on one side and even-numbered columns are not displayed. In this case, according to the above embodiment, the pixels included in the even-numbered columns (second column, fifth row, fourth column, third row) are not displayed. On the other hand, according to this modification, the color information of the pixels included in the even-numbered columns (non-display return path) is reflected in the color information of adjacent pixels in the odd-numbered columns (the forward path to be displayed) corresponding to the previous column. In the example shown in FIG. 20, the color information of the pixel in the second column and the fifth row is reflected in the color information of the pixel in the first column and the fifth row, and the color information of the pixel in the fourth column and the third row is reflected in the pixel in the third column and the third row. Reflected in the color information. Therefore, the user can estimate or grasp the information included in the return path based on the display image.

61 CPU
70 Image signal processor 79 Vertical scanning system 81 Horizontal scanning system 200 Head mounted display 220 BD sensor 230 BD signal detection circuit 240 Optical sensor 250 Delay detection circuit 300 Image information 310 Image data 320 One-side scanning information

Claims (8)

Reference signal generating means for generating a reference signal for determining the display start timing of the image;
In accordance with the reference signal generated by the reference signal generating means, a light emitting means for generating and emitting a light beam corresponding to an image signal;
Optical scanning means for displaying the image on a subject by two-dimensionally scanning the light beam emitted from the light emitting means in a main scanning direction and a sub-scanning direction substantially orthogonal to the main scanning direction;
In the display device in which the optical scanning unit can selectively execute reciprocating scanning for alternately scanning the forward path and the backward path in the main scanning direction and one-side scanning for scanning only one of the forward path and the backward path,
Based on the image, range specifying means for specifying a one-side scanning range that is a range to be displayed by the one-side scanning;
One-side scanning signal generating means for generating a one-side scanning signal that is the image signal for executing the one-side scanning with respect to the one-side scanning range specified by the range specifying means;
A display device comprising: a reciprocating scanning signal generating unit configured to generate a reciprocating scanning signal which is the image signal for executing the reciprocating scanning with respect to a range different from the one-side scanning range in the image. . A delay amount detecting means for detecting a delay amount of the display start timing with respect to the reference signal generated by the reference signal generating means,
The display device according to claim 1, wherein the range specifying unit specifies the one-side scanning range when the delay amount detected by the delay amount detection unit is outside a predetermined range. Range information acquisition means for acquiring range information indicating the position, shape, and size of the one-side scanning range in the image;
The display device according to claim 1, wherein the range specifying unit specifies the one-side scanning range based on the range information acquired by the range information acquisition unit.   The display device according to claim 3, wherein the range information acquisition unit acquires the range information from image information including the image and the range information.   5. The display device according to claim 1, wherein the image signal includes the range information in an invalid scanning period other than an effective scanning period in which image display is actually performed. Character information specifying means for specifying character information included in the image based on the image information,
The range information acquiring unit acquires the position, shape, and size of a range including the character information specified by the character information specifying unit as the range information. Display device. Comprising one-sided scanning setting means for setting whether or not to perform the one-sided scanning,
The display device according to claim 1, wherein the range specifying unit specifies the one-side scanning range when the one-side scanning setting unit is set to execute the one-side scanning.   When the one-side scanning signal displays the image in the forward scan, the color information of the pixel displayed in the forward pass is complemented with the color information of the pixel corresponding to the return pass adjacent to the forward pass, The color information of the pixel displayed on the return path is complemented with the color information of the pixel corresponding to the forward path adjacent to the return path when the image is displayed in the return path scan. The display apparatus in any one of.

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