Information projection display device

Abstract

An information projection display device according to the present disclosure comprises: a light source having a plurality of light-emitting elements; a light source drive unit that generates a drive signal causing the plurality of light-emitting elements to emit light; an optical system that receives light from the light source and projects the light; a shift unit that varies the position of the projected light; a signal processing unit that determines an operating state of the plurality of light-emitting elements and outputs a signal to the light source drive unit; and a shift signal generation unit that generates a drive signal for the shift unit. An arrangement of the projected light and an arrangement of the plurality of light-emitting elements correspond to one another. Let a prescribed projection position be the position at which the light of a first light-emitting element with lower luminous efficacy than another light-emitting element is projected. Among the other light-emitting elements, let a second light-emitting element be one or more light-emitting elements that emit light at the prescribed projection position due to the shift unit varying the position of the light, and let a third light-emitting element be a light-emitting element that emits light at a position different from the prescribed projection position. Given the above, the intensity of light emitted by the second light-emitting element is higher than the intensity of light emitted by the third light-emitting element.

Description

Information projection display device

[0001] The present disclosure relates to an information projection display device that can be adapted to illuminate an object or display information.

[0002] In recent years, advances in LED (light-emitting diode) technology have led to the development of devices for displaying information called micro-LEDs. Patent Document 1 discloses a micro-LED device in which a large number of light-emitting elements are monolithically formed.

[0003] When such micro LEDs are applied to car headlights, it becomes possible to control the illumination range so as not to dazzle preceding or oncoming vehicles.

[0004] Furthermore, when applied to lighting devices, it becomes possible to freely change the shape, number and edge of the light, as well as to draw the shape of the light freehand, which means that it is no longer just a uniform light, but rather the light has movement, guiding people to their desired location, and the fluctuating effect can enhance the impression when viewing exhibits in art galleries and museums, providing unprecedented value.

[0005] Special Publication No. 2022-523081

[0006] In the lighting devices using the conventional micro LEDs described above, some of the many light-emitting elements may malfunction, resulting in areas that do not emit light, which reduces the quality of the lighting.

[0007] Furthermore, Patent Document 1 discloses a configuration in which a spare light-emitting element is provided in case a defect occurs in the light-emitting element, but providing a spare light-emitting element reduces the resolution and increases costs, which is a problem.

[0008] Therefore, an object of the present disclosure is to provide an information projection display device that can suppress degradation of lighting quality even if a defect occurs in a light-emitting element.

[0009] An information projection display device according to one aspect of the present disclosure includes a light source having a plurality of light-emitting elements each emitting light; a light source drive unit that generates a drive signal to cause the plurality of light-emitting elements of the light source to emit light; an optical system that receives the light emitted from the light source and projects the light at a desired position; a shift unit that repeatedly changes the position of the light projected from the optical system within a desired range; a signal processing unit that determines the operating state of the plurality of light-emitting elements based on information to be displayed and outputs a signal to the light source drive unit; and a shift signal generation unit that generates a signal to drive the shift unit, and and the arrangement of the plurality of light-emitting elements in the light source have a corresponding relationship with each other, the light source includes a first light-emitting element having a lower light-emitting efficiency than the other light-emitting elements, a position corresponding to the first light-emitting element at the desired position is set as a predetermined projection position, and the shift unit changes the position of the light, so that one or more light-emitting elements among the other light-emitting elements that emit light to the predetermined projection position are set as second light-emitting elements, and multiple light-emitting elements that emit light to a position different from the predetermined projection position are set as third light-emitting elements, the intensity of light emitted by the second light-emitting element is higher than the intensity of light emitted by the third light-emitting element.

[0010] According to the present disclosure, it is possible to provide an information projection display device that can suppress degradation of lighting quality even if a defect occurs in a light emitting element.

[0011] FIG. 1 is a configuration diagram of an information projection display device according to Embodiment 1. FIG. 2 is a configuration diagram of a light source included in the information projection display device according to Embodiment 1. FIG. 3A is a diagram illustrating the operation of the information projection display device according to Embodiment 1. FIG. 3B is a diagram illustrating the operation of the information projection display device according to Embodiment 1. FIG. 3C is a diagram illustrating the operation of the information projection display device according to Embodiment 1. FIG. 4 is a diagram illustrating the operation of the information projection display device according to Embodiment 1. FIG. 5 is a diagram illustrating the operation of the information projection display device according to Embodiment 2. FIG. 6 is a diagram illustrating the operation of the information projection display device according to Embodiment 3. FIG. 7 is a diagram illustrating the operation of the information projection display device according to Embodiment 4. FIG. 8 is a configuration diagram of an information projection display device according to Embodiment 5. FIG. 9 is a diagram illustrating the configuration of an information projection display device according to Embodiment 6. FIG. 10 is a diagram illustrating the configuration of a photodetector included in the information projection display device according to Embodiment 6. FIG. 11 is a diagram illustrating the configuration of an information projection display device according to Embodiment 7.

[0012] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. However, more detailed description than necessary may be omitted. For example, detailed description of well-known matters or redundant description of substantially identical configurations may be omitted. This is to avoid unnecessary redundancy in the following description and to facilitate understanding by those skilled in the art.

[0013] The accompanying drawings and the following description are provided to enable those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter described in the claims.

[0014] 1 is a diagram showing the configuration of an information projection display device according to Embodiment 1. The information projection display device 100 is made up of an information projection display head device 101 and a control unit 201.

[0015] The information projection display head device 101 includes a light source 111 , a shift unit 121 , a lens 131 , and a lens 151 .

[0016] The control unit 201 includes a light source driving unit (LDD) 211 , a shift signal generating unit (PSGEN) 221 , a signal processing unit (SIGP) 231 , and a memory unit (MEM) 241 .

[0017] FIG. 2 is a diagram showing the configuration of a light source included in an information projection display device. As shown in FIG. 2, the light source 111 has a plurality of light-emitting elements 1a arranged in a matrix. The light-emitting elements 1a are light-emitting diodes (LEDs) made of gallium nitride and indium-doped gallium nitride, which are compound semiconductors, and emit blue light. Although not shown, a phosphor that receives the blue light and emits yellow light is provided near the light-emitting surface of the light-emitting element 1a. The light-emitting element 1a is configured so that the blue light emitted from the light-emitting element 1a and the yellow light emitted from the phosphor combine to emit divergent white light.

[0018] In order to avoid cluttering the drawing, Figure 2 shows six light-emitting elements 1a in each direction, for a total of 36 light-emitting elements 1a. However, in this embodiment, the light source 111 has 64 light-emitting elements 1a in each direction, for a total of 16,384 light-emitting elements 1a. The size W of one light-emitting element 1a is 45 microns, and the period pt of the arrangement of the light-emitting elements 1a is 50 microns. In other words, there is a separation region of 5 microns between two light-emitting elements 1a. This separation region does not emit light.

[0019] The plurality of light-emitting elements 1a each emit light. The light-emitting state of each of the plurality of light-emitting elements 1a can be changed independently, and characters, images, patterns of desired shapes, etc. can be irradiated or displayed.

[0020] The method of causing each of the plurality of light-emitting elements 1a to emit light may be to provide a circuit that controls light emission individually for each of the light-emitting elements 1a, or to use a driving method such as an active matrix driving method or a passive matrix driving method. Since any method for controlling light emission is applicable, detailed description thereof will be omitted here.

[0021] Divergent light 71 emitted from light source 111 is received by lens 131 and then converted into convergent light by lens 151. Light 71 converted into convergent light by lens 151 is projected onto projection surface 301. As a result, an image having a shape corresponding to the light emitting states of the multiple light emitting elements 1a of light source 111 is projected onto projection surface 301.

[0022] The light emitting state of the light emitting element 1a of the light source 111 is controlled by a light source driving unit 211 of the control unit 201. An information data ID, which is data of information to be displayed, is input from an information data input unit 261 of the control unit 201.

[0023] The signal processing unit 231 receives the information data ID input to the input unit 261, and generates light source drive data LD for causing the light emitting element 1a of the light source 111 to emit light in a desired state.

[0024] Furthermore, the signal processing unit 231 drives the shift unit 121 using the shift signal generation unit 221. The signal output from the shift signal generation unit 221 is a square wave signal that moves the light source 111 to a desired position, and the position of the light source 111 moves according to the voltage value of the square wave signal.

[0025] The information projection display device 100 functions as long as it can optically equivalently move the light-emitting positions of the multiple light-emitting elements 1a of the light source 111. Therefore, it is not necessarily limited to moving the light source 111, but it only needs to have a function of optically equivalently moving the optical axis of the optical path from the light source 111 to the projection surface. In the information projection display device 100, the light source 111 is moved using the shift unit 121, and the light-emitting positions of the multiple light-emitting elements 1a of the light source 111 also change according to the change in the position of the light source 111.

[0026] The signal processing unit 231 also generates shift unit driving data DD, which is data for driving the shift unit 121 to move the light source 111 to a desired position at a desired time.

[0027] The camera 302 is disposed at a location separate from the information projection display device 100, and observes the projection surface 301 onto which the information projection display device 100 projects light. This separate location is a location where, during the process of assembling the information projection display device 100, the light-emitting state of the light-emitting elements 1a of the light source 111 of the information projection display device 100 can be confirmed and an image projected onto the projection surface 301 can be captured to generate correction data CD. The camera 302 is set to a resolution that allows the spacing between the multiple light-emitting elements 1a of the light source 111 to be distinguished in the image projected onto the projection surface 301. By observing the projection surface 301 with the camera 302, the light-emitting characteristics of each of the multiple light-emitting elements 1a of the light source 111 can be grasped.

[0028] The correction data CD is generated using an image obtained by emitting light from the plurality of light-emitting elements 1a of the light source 111 and observing the light 71 projected onto the projection surface 301 with the camera 302. The correction data CD is used to correct differences in brightness caused by variations in the light-emitting characteristics of the plurality of light-emitting elements 1a of the light source 111. The correction data CD is information about the position and light-emitting characteristics of each light-emitting element 1a. The correction data CD is input to the signal processing unit 231.

[0029] The correction data CD is input from the correction data input unit 271. The information data ID and the correction data CD are input to the signal processing unit 231. The signal processing unit 231 modifies the light source driving data LD based on the correction data CD so as to correct differences in the characteristics of the light emitting elements 1a in the light source driving data LD. Information related to the correction data CD input to the signal processing unit 231 is stored in the memory unit 241.

[0030] By providing the memory unit 241, it is possible to input the correction data CD only once when assembling or adjusting the information projection display device 100, and thereafter, the characteristics of the light source can be appropriately corrected without inputting the correction data CD again.

[0031] The shift unit 121 is configured using a general electromagnetic actuator.

[0032] 3A to 3C are schematic diagrams showing the operation of the information projection display device according to this embodiment.

[0033] 3A to 3C, H and V each indicate directions in a plane parallel to the light source 111. Furthermore, 0 to 7 in the H direction and a to f in the V direction each indicate the location of the light source 111. The length of one of 0 to 7 in the H direction and a to f in the V direction is the same as the size of the light-emitting element that constitutes the light source 111. Therefore, when the light-emitting element 1a at the bottom left of the light source 111 moves from position 1 in the H direction to position 2 in the H direction, this indicates that the light source 111 has moved by the size of one pixel.

[0034] In the light source 111, the light-emitting element 1b shown in black, which is the third from the top in the V direction and the third from the left in the H direction, has a defect and does not emit light even when current is passed through it.

[0035] On the other hand, the other light-emitting elements 1a are light-emitting elements that emit light normally when a current is passed through them. For ease of understanding, it is assumed that the normally emitting light-emitting elements 1a emit light with the same intensity.

[0036] 3A shows the case where the light source 111 is at a first position Pos1 indicating the initial position, and FIG. 3B shows the case where the light source 111 is at a second position Pos2. The second position Pos2 is to the right of the first position Pos1 in the H direction by a distance equivalent to one light-emitting element, i.e., 50 microns in this embodiment.

[0037] The position of the light source 111 in the H direction is changed at predetermined time intervals by the shift unit 121. Here, the time interval is set to 10 milliseconds. t represents relative time, and if time t0 is the start time, 0 milliseconds, time t1 is 10 milliseconds after time t0, time t2 is 20 milliseconds after time t0, and time t3 is 30 milliseconds after time t0. The shift unit 121 repeatedly moves the light source 111 between the first position Pos1 and the second position Pos2 at regular time intervals.

[0038] The light emitting intensity I of the light emitting element 1a shown by diagonal hatching in the light source 111 is set as a normal light emitting intensity, which is set as 1.

[0039] As shown in Figure 3A, when the light source 111 is at the first position Pos1, the emission intensity I of the light-emitting element adjacent to the right of the non-emitting light-emitting element 1b is doubled from its normal emission intensity. Similarly, the emission intensity I of the six light-emitting elements aligned in the V direction on the left edge of the light source 111 is also doubled from its normal emission intensity. The light-emitting element whose emission intensity I is doubled is shown in white and is designated as light-emitting element 1c. At this time, the emission intensity I of the other light-emitting elements 1a of the light source 111 is 1, which is the normal emission intensity.

[0040] 3B , when the light source 111 is at the second position Pos2, the light-emitting element 1c adjacent to the left of the non-emitting light-emitting element 1b has its light-emitting intensity doubled from the normal light-emitting intensity I. Similarly, the six light-emitting elements aligned in the V direction at the right end of the light source 111 also have their light-emitting intensity I increased to twice the normal light-emitting intensity. At this time, the light-emitting elements 1a at other positions of the light source 111, including the light-emitting element whose light-emitting intensity was doubled when the light source 111 was at the first position Pos1, have their light-emitting intensity set to 1, which is the normal light-emitting intensity.

[0041] 3C shows a state in which the light emission intensity I when the light source 111 is at the first position Pos1 and when it is at the second position Pos2 is averaged over a time longer than the cycle of repeated driving by the shift unit 121. Because the human eye cannot distinguish movement above a certain speed, it appears to a human that the light source 111 is emitting light in the state shown in FIG.

[0042] That is, by moving the light source 111 using the shift unit 121 and further increasing the light emission intensity of the light-emitting element 1a adjacent to the non-emitting light-emitting element 1b, the light quantity that is insufficient due to the non-emitting light-emitting element 1b can be compensated for, and the influence of the non-emitting light-emitting element 1b can be reduced.

[0043] Since the position of the light source 111 is shifted in the H direction by the distance of one light-emitting element by the shift unit 121, the light source 111 is recognized as being larger by one light-emitting element in the H direction, i.e., as being composed of six light-emitting elements in the V direction and seven light-emitting elements in the H direction.

[0044] Furthermore, at the location where the non-emitting light-emitting element 1b is located, the adjacent light-emitting element 1c is shifted by the shift section 121, and the light emission intensity of the light-emitting element 1c is increased at the timing when the light-emitting element 1c is positioned at the location where the light-emitting element 1b is located, thereby making up for the lack of light due to the light-emitting element 1b not emitting light.

[0045] Furthermore, when actually displaying a pattern, image, or the like, the data to be displayed is shifted in the opposite direction to the movement of the shift unit 121 in accordance with the movement of the shift unit 121. This prevents blurring of the pattern, image, or the like to be displayed, making it possible to stably display the desired image.

[0046] 4 is a diagram showing the timing at which the light emitting element of the light source 111 of the information projection display device emits light. Pos indicates the position of the light source 111, and Mov indicates that the position of the light source 111 is moving from the first position Pos1 to the second position Pos2 or from the second position Pos2 to the first position Pos1.

[0047] I is the light emission intensity of the light emitting element, and schematically shows whether the light emitting element is emitting light or not.

[0048] F indicates the time allocated to display one image or pattern. F1 is the time allocated to display one image or pattern, and F2 is the time allocated to display another image or pattern. Of course, F1 and F2 may be the same image or pattern, but for ease of understanding, it is assumed here that different images or patterns are displayed in F1 and F2.

[0049] Although not only F1 and F2 but also other steps continue in sequence, it is not possible to show all of them in FIG. 4, so only F1 and F2 are shown.

[0050] When the light source 111 is located at a first position Pos1, the light emitting element of the light source 111 is made to emit light, and when the light source 111 starts to move from the first position Pos1 to the second position Pos2, the light emitting element is temporarily made not to emit light.

[0051] The light emitting element remains off while the light source 111 moves from the first position Pos1 to the second position Pos2. When the light source 111 reaches the second position Pos2, the light emitting element is made to emit light again.

[0052] Similarly, at the timing when the light source 111 starts to move from the second position Pos2 to the first position Pos1, the light emitting element is temporarily made not to emit light.

[0053] The light emitting element remains off while the light source 111 moves from the second position Pos2 to the first position Pos1. When the light source 111 reaches the first position Pos1, the light emitting element is made to emit light again.

[0054] That is, the light emitting element of the light source 111 emits light only when it is located at the desired first position Pos1 or second position Pos2. This operation suppresses crosstalk, which occurs when the light emission pattern of an adjacent light emitting element interferes with the displayed pattern or image, thereby providing the information projection display device 100 with the ability to display clear patterns, images, etc.

[0055] The cycle of the repeating operation of the shift unit 121 is 20 milliseconds, from t0 to t2. Furthermore, the time allocated to displaying one image or pattern is also the same 20 milliseconds. In other words, the cycle of switching the image or pattern display is also 20 milliseconds. The cycle of the repeating operation of the shift unit 121 and the cycle of switching the image or pattern display are the same and synchronized, and the signal processing unit (SIGP) 231 synchronizes the two cycles.

[0056] By making the cycle of the repeating operation of the shift unit 121 the same as the cycle of switching the image or pattern display, the information projection display device 100 can project high-quality images or patterns with little fluctuation. Furthermore, since the frequency of switching the displayed image or pattern can be minimized, signal processing related to the displayed image or pattern is simplified, resulting in an information projection display device 100 with low power consumption.

[0057] [1-2. Effects] It is possible to provide an information projection display device 100 that can reduce degradation in the quality of illumination for projecting patterns, images, etc., even if the light source 111 has light-emitting elements 1b that do not emit light.

[0058] Second Embodiment [2-1. Configuration] The configuration of the information projection display device shown in the second embodiment is the same as the configuration of the information projection display device shown in the first embodiment.

[0059] The difference between the information projection display device shown in the first embodiment and the information projection display device shown in the second embodiment is the timing at which the light emitting elements of the light source 111 emit light.

[0060] FIG. 5 is a diagram showing the timing at which the light emitting elements of the light source 111 of the information projection display device shown in the second embodiment emit light.

[0061] In the information projection display device 100 shown in the first embodiment, the light emitting element of the light source 111 is caused to emit light only when the light emitting element is located at the desired first position Pos1 or second position Pos2.

[0062] On the other hand, in the information projection display device 100 shown in the second embodiment, the light emitting element of the light source 111 is made to emit light not only when it is located at the desired first position Pos1 or second position Pos2, but also for a short time after the movement of the light source 111 begins and from a short time before the light source 111 reaches the desired position and completes its movement. In Figure 5, the parts where the timing of emission is different from that of the first embodiment are indicated by hatching.

[0063] [2-2. Effects] Even if the light source 111 has light-emitting elements 1b that do not emit light, it is possible to provide an information projection display device 100 that can reduce degradation in the quality of the illumination that projects patterns, images, etc.

[0064] Furthermore, if the projection optical system has high resolution, the non-emitting areas between adjacent light-emitting elements that make up the light source 111 will be visible in the projected image, degrading the image quality. However, by emitting light from the light source 111 for a predetermined period after the movement starts and before the movement ends, it is possible to make the non-emitting areas invisible. In other words, the information projection display device 100 can project patterns, images, etc. with even higher quality.

[0065] Furthermore, the longer the light emission time, the brighter the information projection display device 100 becomes.

[0066] Furthermore, the light emission intensity when moving may be set higher than the light emission intensity when stationary, in which case the influence of non-light emitting areas can be reduced more effectively.

[0067] Furthermore, although the shift unit 121 has been described as moving one period of the arrangement of the light-emitting elements, if it is only necessary to reduce the influence of the non-light-emitting regions of the light source 111, the movement of the shift unit may be narrowed to a range corresponding to the non-light-emitting regions. In this way, it is possible to provide an information projection display device 100 that consumes less power.

[0068] Third Embodiment [3-1. Configuration] The configuration of the information projection display device shown in the third embodiment is the same as the configuration of the information projection display device shown in the first embodiment.

[0069] The difference between the information projection display device shown in the first embodiment and the information projection display device shown in the third embodiment is the timing at which the light emitting elements of the light source 111 emit light.

[0070] FIG. 6 is a diagram showing the timing at which the light emitting elements of the light source 111 of the information projection display device shown in the third embodiment emit light.

[0071] In the information projection display device 100 shown in the first embodiment, the light emitting element of the light source 111 is caused to emit light only when the light emitting element is located at the desired first position Pos1 or second position Pos2.

[0072] On the other hand, in the information projection display device 100 shown in the third embodiment, the light emitting element of the light source 111 is made to emit light not only when the light emitting element is located at the desired first position Pos1 or second position Pos2, but also while the shift unit 121 is moving the light source 111. In Fig. 6, hatched areas indicate areas where the timing of emission is different from that of the first embodiment.

[0073] In FIG. 6, the emission intensity of the light emitting elements of the light source 111 is not shown, but the emission intensity of the light emitting element 1c adjacent to the light emitting element 1b is changed to reduce the influence of the light emitting element 1b that does not emit light.

[0074] Because the light-emitting elements are continuously emitting light, the resolution of the projected image decreases according to the amount by which the light source 111 is shifted by the shift unit 121. If the decreased resolution is acceptable, the information projection display device 100 is effective, and the information projection display device 100 becomes brighter because the light-emitting time of the light-emitting elements becomes longer.

[0075] [3-2. Effects] It is possible to provide an information projection display device that can reduce degradation in the quality of illumination for projecting patterns, images, etc., even if the light source has a light-emitting element that does not emit light.

[0076] Furthermore, it is possible to provide an information projection display device 100 that is brighter than the information projection display device shown in the second embodiment.

[0077] Fourth Embodiment [4-1. Configuration] The configuration of the information projection display device shown in the fourth embodiment is the same as the configuration of the information projection display device shown in the first embodiment.

[0078] The information projection display device shown in the first embodiment differs from the information projection display device shown in the fourth embodiment in the movement of the shift section 121 and the timing at which the light emitting elements of the light source 111 emit light.

[0079] FIG. 7 is a diagram showing the timing at which the light emitting elements of the light source 111 of the information projection display device shown in the fourth embodiment emit light.

[0080] In the information projection display device 100 shown in the first embodiment, a rectangular wave signal is input from the shift signal generation unit 221 to the shift unit 121, and the shift unit 121 keeps the light source 111 stationary at the first position Pos1 and the second position Pos2 for a predetermined time, and causes the light emitting element of the light source 111 to emit light when the light emitting element is located at the desired first position Pos1 or second position Pos2.

[0081] On the other hand, in the information projection display device 100 shown in the fourth embodiment, a sine wave signal is input from the shift signal generation unit 221 to the shift unit 121, and the shift unit 121 constantly moves the light source 111 in accordance with changes in the voltage of the sine wave signal.

[0082] The shift unit 121 moves the light source 111 to a first position Pos1 near the maximum value of the sine wave signal, and moves the light source 111 to a second position Pos2 near the minimum value of the sine wave signal. Although the shift unit 121 constantly moves the light source 111, the movement of the light source is slow near the maximum and minimum values ​​of the sine wave signal, and the operation is essentially the same as if the light source were stationary.

[0083] The light emitting element of the light source 111 emits light near the maximum and minimum values ​​of the sine wave signal.

[0084] Making the signal that drives the shift unit 121 a sine wave smooths the operation of the shift unit 121. This prevents the shift unit 121 from generating unnecessary vibrations that tend to occur when the shift unit 121 transitions from moving to stationary when operated with a square wave, resulting in the information projection display device 100 being able to project clear images.

[0085] Furthermore, when the frequency of the sine wave signal input to the shift unit 121 is brought close to the structural primary resonance frequency of the shift unit 121, the information projection display device 100 is less susceptible to the effects of external shocks and vibrations, thereby enabling the projection of images with minimal shaking even when subjected to external shocks or vibrations.

[0086] [4-2. Effects] It is possible to provide an information projection display device 100 that can reduce degradation in the quality of illumination for projecting patterns, images, etc., even if the light source 111 has light-emitting elements 1b that do not emit light.

[0087] Fifth Embodiment [5-1. Configuration] FIG. 8 is a diagram showing the configuration of an information projection display device according to a fifth embodiment.

[0088] The information projection display device 100A shown in the fifth embodiment is composed of an information projection display head device 102 and a control unit 202.

[0089] In the information projection display device 100 shown in the first embodiment, the camera 302 is provided in a location different from the information projection display head device 101, and the characteristics of the light source 111 are grasped and correction data CD is generated when the information projection display device 100 is assembled or adjusted. In the information projection display device 100A shown in this embodiment, the camera 181 is built into the information projection display head device 102. In other words, the camera 181 is built into the information projection display device 100A.

[0090] The camera 181 can be used to correct variations and defects in the light emitting elements 1a of the light source 111 in the same manner as in the first embodiment.

[0091] The signal output from the camera 181 is input to a photodetection data processing unit (PDP) 281 included in the control unit 202 .

[0092] The light detection data processing unit 281 generates a signal that makes it easy to grasp the light emission state of the light source 111 based on the signal from the camera 181. The signal generated by the light detection data processing unit 281 is input to the signal processing unit 232.

[0093] The signal processing unit 232 generates light source drive data LD, which is data used to make the light emitting elements 1a of the light source 111 emit light in a desired state. At that time, the signal processing unit 232 also generates correction data CD that corrects variations in the light emission characteristics of the light emitting elements 1a that make up the light source 111, using a signal from the light detection data processing unit 281. The signal processing unit 232 also generates shift unit drive data DD that uses the shift signal generation unit 221 to move the shift unit 121 to a desired position at a desired time.

[0094] By providing a memory unit 241, the correction data CD generated by the signal processing unit 232 when assembling or adjusting the information projection display device 100A is stored in the memory unit 241 only once, and thereafter, brightness variations caused by variations in the light-emitting characteristics of the light-emitting elements of the light source can be appropriately corrected without having to input the correction data CD.

[0095] Furthermore, camera 181 is built into information projection display head device 102. As a result, even if projection surface 301 is oriented obliquely with respect to the light projected from information projection display device 100A, has a complex shape that is not flat, or has non-uniform reflectance, by viewing the state of light projected onto projection surface 301 with camera 181, it becomes possible to appropriately make desired corrections suited to the target even after assembling or adjusting information projection display device 100A.

[0096] [5-2. Effects] It is possible to provide an information projection display device 100A that can reduce degradation in the quality of illumination for projecting patterns, images, etc., even if the light source 111 has light-emitting elements 1b that do not emit light, or even if the characteristics of the light-emitting elements change over time.

[0097] Sixth Embodiment [6-1. Configuration] FIG. 9 is a diagram showing an example of the configuration of an information projection display device according to a sixth embodiment.

[0098] The information projection display device 100B shown in the sixth embodiment is composed of an information projection display head device 103 and a control unit 203.

[0099] The information projection display device 100B shown in the sixth embodiment differs from the information projection display device 100A shown in the fifth embodiment in that it does not have a camera 302, but does have a light branching element 141 and a photodetector 171.

[0100] Divergent light 71 emitted from light source 111 passes through lens 131 and then passes through lens 151 to become convergent light. The operation of this path is similar to that of the information projection display device 100 shown in the first and second embodiments.

[0101] In the information projection display device 100B shown in the sixth embodiment, a portion of the light 71 that has passed through the lens 131 is branched by the light branching element 141. The light 71 branched by the light branching element 141 becomes light 72, which is collected by the lens 161 and then received by the photodetector 171.

[0102] FIG. 10 shows a schematic configuration of the photodetector 171. The photodetector 171 has one light receiving section 172, and light 72 collected by the lens 161 is received by the light receiving section 172. The photodetector 171 outputs a signal according to the amount of light received for each region corresponding to each light emitting element 1a of the light source 111. The photodetector 171 has a general configuration made of silicon, and outputs a current proportional to the amount of light received as a detection signal. How to use a photodetector using silicon is a well-known general matter, so details will not be shown here. How to use a general photodetector, such as applying a reverse bias voltage, can also be applied to the present disclosure.

[0103] As shown in FIG. 9, the signal output from the photodetector 171 is input to a photodetection data processing unit 282 included in the control unit 203 .

[0104] The light detection data processing unit 282 generates a signal that makes it easy to grasp the light emission state of the light source 111 based on the signal from the light detector 171. The signal generated by the light detection data processing unit 282 is input to the signal processing unit 233.

[0105] The photodetector 171 has one light receiving unit, whereas the light source 111 has multiple light emitting elements. In order to grasp the light emitting characteristics of the multiple light emitting elements, each light emitting element emits light at a different timing in sequence.

[0106] The signal processing unit 233 generates light source drive data LD for causing the light emitting elements 1a of the light source 111 to emit light in a desired state. At that time, the signal processing unit 233 also generates correction data CD for correcting the characteristics of the light emitting elements that make up the light source 111, using a signal from the light detection data processing unit 282. The signal processing unit 233 also generates shift unit drive data DD for using the shift signal generation unit 221 to move the shift unit 121 to a desired position at a desired time.

[0107] By providing a memory unit 241, the correction data CD generated by the signal processing unit 232 when assembling or adjusting the information projection display device is stored in the memory unit 241 only once, and thereafter the characteristics of the light source can be appropriately corrected without inputting the correction data CD.

[0108] Furthermore, since the photodetector 171 is built into the information projection display head device 103, even if the characteristics of the light emitting elements change over time, new correction data CD can be generated as needed.

[0109] The signal processing unit 233 also generates shift unit driving data DD, which is data used to move the shift unit 121 to a desired position at a desired time using the shift signal generating unit 221 .

[0110] [6-2. Effects] It is possible to provide an information projection display device 100B that can reduce degradation in the quality of illumination for projecting patterns, images, etc., even if the light source 111 has light-emitting elements 1b that do not emit light, or even if the characteristics of the light-emitting elements change over time.

[0111] Seventh Embodiment [7-1. Configuration] FIG. 11 is a diagram showing the configuration of an information projection display device according to a seventh embodiment.

[0112] The information projection display device 100C shown in the seventh embodiment is composed of an information projection display head device 104 and a control unit 204.

[0113] The configuration of the information projection display device shown in the seventh embodiment is generally similar to the configuration of the information projection display device shown in the first embodiment.

[0114] The information projection display device 100 shown in the first embodiment and the information projection display device 100C shown in the seventh embodiment differ in the following three points.

[0115] (1) Configuration of the shift unit 122 that shifts the light-emitting position of the light-emitting element of the light source 111 The shift unit 121 of the information projection display device 100 shown in the first embodiment is configured with an electromagnetic actuator using a coil and a magnet, whereas the shift unit 122 of the information projection display device 100C shown in the seventh embodiment is configured with a piezoelectric actuator using a piezoelectric element made of lead zirconate titanate (PZT).

[0116] (2) Method of moving the light-emitting position of the light-emitting element of the light source 111 In the information projection display device shown in the first embodiment, the light source 111 itself is moved using the shift unit 121. On the other hand, in the information projection display device 100C shown in the seventh embodiment, the position of the light source 111 is fixed, and the light 71 emitted from the light-emitting element of the light source 111 is received and reflected by the mirror 142, and the angle of the mirror 142 is changed by the shift unit 122, thereby optically moving the light-emitting position of the light-emitting element of the light source 111.

[0117] (3) Configuration of the Shift Signal Generator that Outputs a Signal to Drive the Shift Unit The shift unit 121 of the information projection display device 100 shown in the first embodiment is an electromagnetic actuator. In contrast, the shift unit 122 of the information projection display device 100C shown in the seventh embodiment is a piezoelectric element. Therefore, the voltage, current, and waveform of the signal used to drive the shift units 121 and 122 are different. The shift signal generator 222 outputs a drive signal suitable for the piezoelectric element.

[0118] An actuator using a piezoelectric element is a well-known general structure, and a detailed description thereof will be omitted.

[0119] The operation of the information projection display device 100C according to the seventh embodiment is similar to that of the information projection display device 100 according to the first embodiment.

[0120] [7-2. Effects] Even if the light source 111 has light-emitting elements 1b that do not emit light, the information projection display device 100C can be provided, which can reduce degradation in the quality of the illumination that projects patterns, images, etc.

[0121] (Other Embodiments) Note that the lens 131 and the lens 151 are general projection optical systems, and a simple configuration using two lenses is shown to facilitate understanding of the present disclosure. Depending on the required optical performance, a single finite lens may be used, or a large number of lenses, such as 10, may be used to provide high optical performance. The effect of the present disclosure, which avoids or reduces the effects of defective light-emitting elements, can be achieved regardless of the optical system used.

[0122] Furthermore, since the lifespan of the light-emitting elements may be shortened if the light-emitting elements are made to emit strong light in synchronization with the movement of the shift section, it is possible to weaken the light-emitting intensity of adjacent light-emitting elements to a level that alleviates the influence of non-emitting light-emitting elements to some extent, rather than completely eliminating the influence of non-emitting light-emitting elements. By doing so, it is possible to provide an information projection display device with a longer lifespan and higher reliability.

[0123] Furthermore, the timing for shifting the shift unit is not limited to 10 milliseconds, and any time interval may be used. From the viewpoint of the response speed of the eye, if the time is set to approximately 50 milliseconds or shorter, the user will experience almost no discomfort and the influence of non-emitting light-emitting elements can be mitigated. This makes it possible to provide an information projection display device capable of projecting attractive images. If the time is set to longer than 50 milliseconds, flicker may be perceived, but the influence of non-emitting light-emitting elements can be mitigated.

[0124] Furthermore, the information projection device is not limited to information display devices generally called projectors, but the effects of the present disclosure can be achieved with any device that projects light, such as ADB (adaptive driving beam, variable light distribution headlamp) headlights for cars and motorcycles, lighting devices with advanced functions, etc.

[0125] Furthermore, although the shift unit is configured using a general electromagnetic actuator and a piezoelectric actuator in the above embodiment, the type of the shift unit does not restrict the operation of the present disclosure. Any type of actuator, such as an electrostatic actuator, or a deflector using an optical element with an electro-optic effect, may be used.

[0126] Furthermore, when an actuator is used, the actuator may be driven at its primary resonance frequency or a frequency close to the primary resonance frequency, which allows operation with less power consumption, thereby reducing the power consumption of the entire information projection display device.

[0127] Furthermore, when the actuator is driven at its primary resonance frequency, the information projection display device is less affected by unintentional external vibrations or shocks and is capable of stably displaying information.

[0128] Furthermore, although the embodiments have been described in which the light source is moved by a shift unit and in which the mirror receives light emitted from the light-emitting element of the light source and moves the mirror, the effects of the present disclosure can be achieved as long as the relative positions of the light source and the optical system are changed, and therefore other components of the optical system may be moved.

[0129] In addition, the light source shown in the present embodiment uses an LED using a compound semiconductor and a phosphor to emit white light, but there are no particular restrictions on the configuration or color of the light source, and it may be a different color, or may be an LED or laser using an organic material. Any light source having multiple light-emitting elements can be applied to the information projection display head device and the information projection display device.

[0130] Furthermore, although the number of light emitting elements 1a constituting the light source 111 is set to 16,384 here, there is no limit to the number of light emitting elements 1a, and any number may be used as long as it is plural.

[0131] Furthermore, even if the data to be displayed is not shifted in the opposite direction to the movement of the shift section in accordance with the movement of the shift section, the resolution of the displayed image, pattern, etc. will decrease, but the effect of reducing the degradation of display quality due to light-emitting elements that do not emit light can be obtained, just as in the case where the data is shifted in synchronization with the movement of the shift section. In this case, data processing is simplified, resulting in an inexpensive information projection display device.

[0132] In addition, to make it easier to understand the operating principle, the movement of the shift unit is shown at two positions separated by a distance equivalent to one light-emitting element in the H direction, but the movement may be performed at positions separated by two or more light-emitting elements, or three or more positions. The longer the movement distance, the easier it is to reduce the influence of light-emitting elements that do not emit light properly, even when there are multiple elements that do not emit light.

[0133] Furthermore, the shift direction of the shift unit may be the V direction instead of the H direction. Also, it may be moved in both the V direction and the H direction. In this case, even if a light source with a line defect in which non-emitting light-emitting elements exist in a line is used, the influence of the non-emitting light-emitting elements can be effectively reduced with a small shift amount.

[0134] Furthermore, there are no restrictions on the waveform of the drive signal that drives the shift section, and various waveforms such as a square wave and a sine wave can be applied as needed.

[0135] When a rectangular wave is used, the optical light emitting position of the light source can be kept stationary for a desired period of time, resulting in an information projection display device capable of projecting bright and clear images.

[0136] Furthermore, a voltage that accelerates the movement speed to shorten the movement time or a variable voltage that smooths the stationary movement to suppress the vibration that tends to occur when changing from movement to stationary may be added to the rising and falling portions of the square wave, thereby providing an information projection display device that can project brighter and clearer images.

[0137] Furthermore, when a sine wave is used, the operation of the shift unit becomes smoother. This prevents the shift unit from generating unnecessary vibrations that tend to occur when the shift unit transitions from moving to stationary when operated with a square wave, resulting in an information projection display device that can project clear images. Furthermore, when the frequency of the sine wave signal input to the shift unit is brought closer to the structural primary resonance frequency of the shift unit, the device becomes less susceptible to external shocks and vibrations, resulting in an information projection display device that can project images with less shaking even when subjected to external shocks or vibrations.

[0138] Furthermore, the intensity of the light-emitting elements may be changed as needed, such as by changing the light-emitting brightness of the light-emitting elements of the light source in response to the movement of the light source, or by increasing the light-emitting intensity for a short period of time, a process known as overdrive. In this case, even when the shift unit is continuously moving, the information projection display device can provide a high-quality, bright projected image, similar to when the shift unit is substantially stationary.

[0139] Alternatively, a single light source driver may sequentially switch the light emission of multiple light-emitting elements. In this case, the switching of the light-emitting element's light-emitting state may be performed at a cycle shorter than the interval at which the image or pattern display is switched. Furthermore, the switching of the light-emitting element's light-emitting state may be synchronized with the switching of the image or pattern display. This results in an information projection display device capable of projecting high-quality images or patterns with little fluctuation. Furthermore, since the frequency of switching the displayed image or pattern can be minimized, signal processing related to the displayed image or pattern is simplified, resulting in an information projection display device with low power consumption.

[0140] Furthermore, the photodetector is not limited to a configuration using silicon, and any configuration may be used as long as it has the property of outputting a signal that reflects the intensity of the received light.

[0141] The photodetector may also have multiple light-receiving elements. By providing the same number of light-receiving elements as the light source's light-emitting elements, correction data can be obtained even when the light-emitting elements of the light source are driven simultaneously, thereby shortening the time required to create the correction data. Furthermore, since the state of the light source can be constantly monitored while the information projection display device is in operation, any changes in the light-emitting characteristics of the light source can be immediately corrected.

[0142] Furthermore, the number of light receiving sections of the photodetector may be multiple but less than the number of light emitting elements, in which case the number of times the light emitting elements are caused to emit light at sequentially shifted timings can be reduced compared to when there is only one light receiving section, thereby shortening the time required to create correction data.

[0143] The following describes the features of the information projection display device described based on the above embodiment.

[0144] <1> A light source having a plurality of light-emitting elements each emitting light; a light source drive unit that generates drive signals to cause the plurality of light-emitting elements of the light source to emit light; an optical system that receives light emitted from the light source and projects the light at a desired position; a shift unit that repeatedly changes the position of the light projected from the optical system within a desired range; a signal processing unit that determines operating states of the plurality of light-emitting elements based on information to be displayed and outputs a signal to the light source drive unit; and a shift signal generation unit that generates a signal to drive the shift unit, wherein an arrangement of the light projected at the desired position and an arrangement of the plurality of light-emitting elements in the light source have a corresponding relationship, the light source includes a first light-emitting element having lower light-emitting efficiency than other light-emitting elements, a position corresponding to the first light-emitting element at the desired position is set as a predetermined projection position, and the shift unit changes the position of the light, so that one or more light-emitting elements that emit light at the predetermined projection position are set as second light-emitting elements, and multiple light-emitting elements that emit light at a position different from the predetermined projection position are set as third light-emitting elements, An information projection display device, wherein the intensity of light emitted by the second light-emitting element is higher than the intensity of light emitted by the third light-emitting element.

[0145] <2> The information projection display device described in <1>, further comprising: an optical branching element that branches the light emitted from the light source; and a photodetector that has a light receiving unit that receives the light branched by the optical branching element and outputs a signal according to the amount of light received by the light receiving unit, and the signal output from the photodetector is used to correct differences in the light emitting efficiency of the plurality of light emitting elements.

[0146] <3> The information projection display device according to <1>, further comprising an imaging unit that captures an image of the light projected from the optical system onto the desired position and outputs a signal corresponding to the amount of light projected onto the desired position, and corrects for differences in luminous efficiency of the plurality of light-emitting elements using the signal output from the imaging unit.

[0147] <4> The information projection display device according to any one of <1> to <3>, wherein the light source driving unit changes the intensity of a driving signal that causes the light source to emit light in accordance with differences in light-emitting efficiency of the plurality of light-emitting elements of the light source.

[0148] <5> The information projection display device according to any one of <1> to <3>, wherein information relating to differences in luminous efficiency of the plurality of light-emitting elements is stored.

[0149] <6> An information projection display device according to any one of <1> to <3>, wherein the light source driving unit sequentially switches the plurality of light-emitting elements of the light source to emit light, and the operation of switching the light-emitting states of the plurality of light-emitting elements is synchronized with the operation of switching the information to be displayed.

[0150] <7> The information projection display device according to <2>, wherein the photodetector has a single light receiving portion.

[0151] <8> The information projection display device according to <2>, wherein the photodetector has a plurality of light receiving portions.

[0152] <9> An information projection display device according to any one of <1> to <3>, wherein the shift unit changes the position of the light, then keeps the position of the light stationary for a certain period of time, and then repeats changing and keeping the position of the light stationary again, and the plurality of light-emitting elements of the light source emit light only when the shift unit is operated so that the position of the light is stationary, and the plurality of light-emitting elements of the light source do not emit light when the shift unit is operated so that the position of the light changes.

[0153] <10> An information projection display device according to any one of <1> to <3>, wherein the shift unit changes the position of the light, then keeps the position of the light stationary for a certain period of time, and then repeats changing and keeping the position of the light stationary again, and the plurality of light-emitting elements of the light source emit light when the shift unit is operated so that the position of the light is stationary, and the plurality of light-emitting elements of the light source also emit light when the shift unit is operated so that the position of the light changes.

[0154] <11> The information projection display device according to any one of <1> to <3>, wherein the shift unit continuously changes the position of the light, and the plurality of light-emitting elements of the light source emit light at a timing when the change in the position of the light becomes slower.

[0155] <12> The information projection display device according to any one of <1> to <3>, wherein the repeating operation of the shift unit and the operation of switching the light emitting states of the plurality of light emitting elements based on the information to be displayed are synchronized.

[0156] In addition, the present disclosure also includes forms obtained by applying various modifications to the embodiments that a person skilled in the art would conceive, and forms realized by arbitrarily combining the components and functions of the embodiments within the scope of the present disclosure.

[0157] The present disclosure is applicable to devices that project light, such as projectors, headlights for cars and motorcycles, lighting devices, etc. In particular, the present disclosure is applicable to information projection display devices that require high-quality information display even when using a light source that includes a defective light-emitting element.

[0158] 1a, 1b, 1c Light emitting element 71, 72 Light 100, 100A, 100B, 100C Information projection display device 101, 102, 103, 104 Information projection display head device 111 Light source 121, 122 Shift unit 131 Lens 141 Light branching element 142 Mirror 151, 161 Lens 171 Photodetector 172 Light receiving unit 181 Camera 201, 202, 203, 204 Control unit 211 Light source driving unit 221, 222 Shift signal generating unit 231, 232, 233 Signal processing unit 241 Storage unit 251 Information data processing unit 261 Information data input unit 271 Correction data input unit 281, 282 Photodetection data processing unit 301 Projection surface 302 Camera CD Correction data ID Information data LD Light source drive data DD Shift section drive data

Claims

1. A display device comprising: a light source having a plurality of light-emitting elements each emitting light; a light source driver that generates drive signals to cause the plurality of light-emitting elements of the light source to emit light; an optical system that receives light emitted from the light source and projects the light onto a desired position; a shift unit that repeatedly changes the position of the light projected from the optical system within a desired range; a signal processor that determines the operating states of the plurality of light-emitting elements based on information to be displayed and outputs a signal to the light source driver; and a shift signal generator that generates signals to drive the shift unit, wherein the arrangement of the light projected onto the desired position and the arrangement of the plurality of light-emitting elements in the light source have a corresponding relationship, the light source includes a first light-emitting element having lower light-emitting efficiency than other light-emitting elements, a position corresponding to the first light-emitting element at the desired position is set as a predetermined projection position, and the shift unit changes the position of the light, so that one or more light-emitting elements that emit light onto the predetermined projection position are set as second light-emitting elements, and multiple light-emitting elements that emit light onto a position different from the predetermined projection position are set as third light-emitting elements, An information projection display device, wherein the intensity of light emitted by the second light-emitting element is higher than the intensity of light emitted by the third light-emitting element.

2. An information projection display device as described in claim 1, further comprising: an optical branching element that branches the light emitted from the light source; and a photodetector having a light receiving unit that receives the light branched by the optical branching element and outputs a signal according to the amount of light received by the light receiving unit, wherein the signal output from the photodetector is used to correct differences in the luminous efficiency of the multiple light-emitting elements.

3. An information projection display device as described in claim 1, further comprising an imaging unit that images the light projected from the optical system onto the desired position and outputs a signal corresponding to the amount of light projected onto the desired position, and the signal output from the imaging unit is used to correct differences in the luminous efficiency of the plurality of light-emitting elements.

4. An information projection display device according to any one of claims 1 to 3, wherein the light source driving unit changes the intensity of the driving signal that causes the light source to emit light in accordance with the difference in luminous efficiency of the plurality of light-emitting elements of the light source.

5. An information projection display device according to any one of claims 1 to 3, which stores information relating to differences in luminous efficiency of the plurality of light-emitting elements.

6. An information projection display device according to any one of claims 1 to 3, wherein the light source driving unit sequentially switches the light emitting elements of the light source to emit light, and the operation of switching the light emitting states of the multiple light emitting elements is synchronized with the operation of switching the information to be displayed.

7. The information projection display device according to claim 2, wherein said photodetector has a single light receiving portion.

8. The information projection display device according to claim 2, wherein the photodetector has a plurality of light receiving portions.

9. An information projection display device as described in any one of claims 1 to 3, wherein the shift unit changes the position of the light, then keeps the position of the light stationary for a certain period of time, and then repeats changing and stopping the position of the light again, and the multiple light-emitting elements of the light source emit light only when the shift unit is operated so that the position of the light is stationary, and the multiple light-emitting elements of the light source do not emit light when the shift unit is operated so that the position of the light changes.

10. An information projection display device as claimed in any one of claims 1 to 3, wherein the shift unit changes the position of the light, then keeps the position of the light stationary for a certain period of time, and then repeats changing and stopping the position of the light again, and the multiple light-emitting elements of the light source emit light when the shift unit is operated so that the position of the light is stationary, and further, the multiple light-emitting elements of the light source emit light when the shift unit is operated so that the position of the light changes.

11. An information projection display device according to any one of claims 1 to 3, wherein the shift unit continuously changes the position of the light, and the plurality of light-emitting elements of the light source emit light at the timing when the change in the position of the light becomes slower.

12. An information projection display device according to any one of claims 1 to 3, wherein the repeating operation of the shifting section and the operation of switching the light emitting states of the plurality of light emitting elements based on the information to be displayed are synchronized.

Images