Head-up display device

Abstract

Provided is a head-up display device that can realize a desired color and can change the brightness of illumination light in accordance with a requested brightness. This HUD device comprises: a plurality of light sources; a light source driver that drives the plurality of light sources; a second control unit that illuminates the plurality of light sources via the light source driver on the basis of illumination control data; and a DMD display element that generates display light on the basis of illumination light emitted by the plurality of light sources. The illumination control data includes control modes Q1, Q2 for generating the illumination light in a brightness corresponding to a requested brightness. The control modes Q1, Q2 have differing brightness ranges BlA, BlB, which partially overlap each other. The second control unit switches modes between the control modes Q1, Q2 when the requested brightness has reached a mode switching value E2, which is located in a non-end part of an overlapping region E1 where the brightness range BlA of the control mode Q1 and the brightness range BlB of the control mode Q2 overlap.

Description

[Technical field]

[0001] The present disclosure relates to a head-up display device. [Background technology]

[0002] For example, the head-up display device described in Patent Document 1 adjusts the brightness of a display image by changing the output of each light source based on an illuminance signal from an illuminance sensor that detects the illuminance around the user. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2016-4121 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the configuration described in Patent Document 1, there is a demand for changing the luminance of a displayed image while realizing a desired color in accordance with the illuminance around the user.

[0005] The present disclosure has been made in consideration of the above-mentioned circumstances, and aims to provide a head-up display device that can change the brightness of illumination light according to a required brightness while achieving a desired color. [Means for solving the problem]

[0006] In order to achieve the above-mentioned object, the head-up display device of the present disclosure comprises a plurality of light sources, a light source driver that drives the plurality of light sources, a control unit that turns on the plurality of light sources via the light source driver based on lighting control data, and a DMD display element that generates display light based on lighting light emitted by the plurality of light sources, wherein the lighting control data includes first and second control modes for generating the lighting light of a luminance according to a requested luminance, the first and second control modes each having a different luminance range that partially overlaps with each other, and the control unit switches between the first and second control modes when the requested luminance reaches a mode switching value that is located at a non-end of an overlapping area where the luminance range of the first control mode and the luminance range of the second control mode overlap. Effect of the Invention

[0007] According to the present disclosure, it is possible to change the luminance of illumination light according to the required luminance while realizing a desired color. [Brief description of the drawings]

[0008] [Figure 1] 1 is a schematic diagram of a vehicle equipped with a head-up display device according to an embodiment of the present disclosure. [Diagram 2] 1 is a schematic diagram of a head-up display device according to an embodiment of the present disclosure. [Diagram 3] FIG. 1 is a schematic diagram of an illumination device according to an embodiment of the present disclosure. [Figure 4] FIG. 2 is a schematic diagram of a display unit according to an embodiment of the present disclosure. [Diagram 5] FIG. 1 is a block diagram of a light source driving device according to an embodiment of the present disclosure. [Figure 6] FIG. 1 is a block diagram of a lighting control data generating device according to an embodiment of the present disclosure. [Figure 7] FIG. 1 is a block diagram of a sample product data acquisition device according to an embodiment of the present disclosure. [Figure 8] FIG. 2 is a block diagram of a shipment data acquisition device according to an embodiment of the present disclosure. [Figure 9] FIG. 2 is a schematic diagram showing the grade to which a sample projector apparatus according to an embodiment of the present disclosure belongs. [Figure 10] 11 is a graph showing RGB output characteristics when generating master data according to an embodiment of the present disclosure. [Figure 11] 11 is a graph showing RGB output characteristics in a high brightness mode when generating product data according to an embodiment of the present disclosure. [Figure 12] 11 is a graph showing RGB output characteristics in a low brightness mode when generating product data according to an embodiment of the present disclosure. [Figure 13] 11 is a graph showing a relationship between a control mode and brightness according to an embodiment of the present disclosure. [Figure 14] FIG. 14 is an enlarged view of a portion of FIG. 13. [Figure 15] 11 is a flowchart of a master data generation process according to an embodiment of the present disclosure. [Figure 16] 13 is a sub-flowchart of a master data generation process according to an embodiment of the present disclosure. [Figure 17] 11 is a flowchart of a product data generation process according to an embodiment of the present disclosure. [Figure 18] 5 is a timing chart showing a waveform pattern of a current supplied to a light source and an operation of a switch in a high brightness mode according to an embodiment of the present disclosure. [Figure 19] 4 is a timing diagram illustrating pulses of current supplied to a light source in a low brightness mode according to an embodiment of the present disclosure. [Figure 20] 1 is a schematic diagram of a variable ND filter device according to an embodiment of the present disclosure. [Figure 21] FIG. 13 is an enlarged view of a portion of FIG. 12 according to an embodiment of the present disclosure. [Figure 22] FIG. 13 is a diagram illustrating a control mode and a DMD duty ratio according to an embodiment of the present disclosure. [Diagram 23] FIG. 13 is a diagram illustrating a control mode and a DMD duty ratio according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] An embodiment of a lighting control data generating method, a lighting control data generating device, and a head-up display device (hereinafter, referred to as a HUD device) according to the present disclosure will be described with reference to the drawings. 1, the HUD device 1 is mounted on the dashboard of a vehicle 2, generates display light L that displays an image, and emits the generated display light L toward a windshield 3. The display light L is reflected by the windshield 3 and reaches a viewer 4 (e.g., a driver of the vehicle 2). This allows the viewer 4 to view a virtual image V displayed in front of the windshield 3. The virtual image V displays various vehicle information such as engine RPM, vehicle speed, etc.

[0010] 2, the HUD device 1 includes a projector device 18, a transmissive screen 50, a light source driving device 5, flat mirrors 55 and 61, a concave mirror 62, a concave mirror driving unit 65, a housing 70, and a light-transmitting unit 71. The projector device 18 includes an illumination device 10 that emits illumination light C, and a display unit 19 that receives the illumination light C and emits display light L.

[0011] The housing 70 is formed, for example, in a box shape from a light-shielding material. The plane mirror 61, the concave mirror 62, and the concave mirror drive unit 65 are housed in the housing 70. The housing 70 has an opening 70a through which the display light L passes. The light-transmitting portion 71 is formed in a curved plate shape made of light-transmitting resin such as acrylic, and is provided so as to close the opening 70a of the housing 70.

[0012] The lighting device 10 generates illumination light C and radiates the generated illumination light C toward the display unit 19. Specifically, as shown in FIG. 3, the lighting device 10 includes a light source group 11, a light combining unit 13, and a light source temperature detection unit 600.

[0013] The light source group 11 is composed of three light sources 11r, 11g, and 11b, each of which is, for example, an LED (Light Emitting Diode). The light source 11r is a red light source and emits red light R. The light source 11g is a green light source and emits green light G. The light source 11b is a blue light source and emits blue light B. Each of the light sources 11r, 11g, and 11b is driven by a light source driving device 5 and emits light at a predetermined light intensity and timing.

[0014] The light combining unit 13 generates illumination light C by aligning the optical axes of red light R, green light G, and blue light B emitted sequentially from the light sources 11r, 11g, and 11b, and emits the generated illumination light C toward the display unit 19. Specifically, the light combining unit 13 includes a reflecting mirror 13a and dichroic mirrors 13b and 13c that reflect light of a specific wavelength and transmit light of wavelengths other than the specific wavelength. The reflecting mirror 13a reflects the incident blue light B toward the dichroic mirror 13b. The dichroic mirror 13b reflects the incident green light G toward the dichroic mirror 13c, while transmitting the blue light B from the reflecting mirror 13a as it is. The dichroic mirror 13c reflects the incident red light R toward the display unit 19, while transmitting the green light G and blue light B from the dichroic mirror 13b. As a result, the dichroic mirror 13c emits, toward the display unit 19, illumination light C that is a combination of the red light R, the green light G, and the blue light B on the same optical axis. The light source temperature detection unit 600 detects the temperatures of the light sources 11r, 11g, and 11b, and outputs the detection results to the light source driving device 5 as a light source temperature signal ST, as shown in FIG.

[0015] As shown in FIG. 4, the display unit 19 includes a prism 15, a light intensity detection section 500, a DMD (Digital Micro mirror Device) display element 30, a projection optical system 40, and a plane mirror . The plane mirror 54 reflects the illumination light C from the illumination device 10 towards the prism 15 . The prism 15 is made of a light-transmitting material and formed in a right-angled isosceles triangular column shape. The prism 15 has an inclined surface 15a facing the plane mirror 54, an orthogonal surface 15b facing the DMD display element 30, and an orthogonal surface 15c facing the projection optical system 40. The illumination light C from the plane mirror 54 reaches the inclined surface 15a of the prism 15. The inclined surface 15a allows most of the illumination light C from the plane mirror 54 to enter the prism 15, and reflects a part of the illumination light C from the plane mirror 54 toward the light intensity detection unit 500. The illumination light C that enters the prism 15 exits from the orthogonal surface 15b of the prism 15 toward the DMD display element 30. The display light L from the DMD display element 30 enters the prism 15 through the orthogonal surface 15b, and is then reflected toward the inclined surface 15a. The display light L reflected by the inclined surface 15a exits from the orthogonal surface 15c toward the projection optical system 40.

[0016] The DMD display element 30 includes a plurality of movable micromirrors 30a. The micromirrors 30a are arranged in a matrix to correspond to the pixels of an image M (see FIG. 2). The micromirrors 30a include electrodes (not shown) and are turned on or off by switching the voltage value applied to the electrodes. When the micromirrors 30a are in the on state, they reflect the illumination light C toward the transmissive screen 50. When the micromirrors 30a are in the off state, they reflect the illumination light C in a direction different from the transmissive screen 50.

[0017] Each micromirror 30a is switched between an on state and an off state by the light source driving device 5 to express a desired color, for example, the luminance and color of each pixel of the image M based on the white illumination light C. Under the control of the light source driving device 5, each micromirror 30a adjusts the luminance of each pixel of the image M by adjusting the DMD duty ratio, which is the period during which the micromirror 30a is in the on state in one frame.

[0018] The light intensity detection unit 500 is composed of a light receiving element having, for example, a photodiode, and is provided at a position where it receives the illumination light C reflected by the prism 15. The light intensity detection unit 500 receives a part of the illumination light C and detects the light intensity of each of the R, G, and B light components constituting the illumination light C in a time-division manner. As shown in Fig. 5, the light intensity detection unit 500 outputs the detection result as a light intensity detection signal SFB to a second control unit 200 (described later) of the light source driving device 5.

[0019] 4, the projection optical system 40 is composed of a concave lens or a convex lens, and magnifies the display light L from the DMD display element 30 through the prism 15, and emits the magnified display light L to the plane mirror 55 shown in FIG. 2. The plane mirror 55 reflects the display light L toward the transmissive screen 50. As shown in FIG. 2, the transmissive screen 50 is composed of a holographic diffuser, a microlens array, a diffusion plate, etc., and displays an image M upon receiving display light L from the projection optical system 40.

[0020] The plane mirror 61 reflects the display light L representing the image M displayed on the transmissive screen 50 toward the concave mirror 62. This plane mirror 61 may be a concave mirror. The concave mirror 62 reflects the display light L from the plane mirror 61 toward the windshield 3. The display light L passes through the light-transmitting portion 71 of the housing 70 and is reflected by the windshield 3 toward the viewer 4.

[0021] The concave mirror driving unit 65 includes a motor and a gear mechanism that transmits the driving force of the motor to the concave mirror 62, neither of which are shown. The concave mirror driving unit 65 rotates the concave mirror 62 about a rotation axis Ax that extends in a direction perpendicular to the plane of the page in Fig. 2. By rotating the concave mirror 62 about the rotation axis Ax, the irradiation position of the display light L with respect to the viewer 4 is adjusted in the height direction.

[0022] As shown in Figure 5, the light source driving device 5 includes a light source driver 300 that supplies a constant current to the light source group 11, an inductor L1, a light source driving unit 43 that drives the light source group 11, a second control unit 200 that controls the light source driving unit 43 and the DMD display element 30, etc., and a first control unit 100 that controls the concave mirror driving unit 65, etc.

[0023] The light source driver 300 is composed of a constant current driver IC (Integrated Circuit) that generates a constant current based on power from an in-vehicle battery (not shown), and is controlled by the second control unit 200. The light source driver 300 supplies a constant current to the light source group 11 based on a command signal from the second control unit 200. When the light source driver 300 receives a command signal from the second control unit 200 to turn off the light source driver 300, the light source driver 300 stops supplying the constant current. The inductor L1 is connected between the light source driver 300 and the light source group 11.

[0024] The light source driving unit 43 includes switches Swr, Swg, Swb, Swc, and Swa, a capacitor C1, and a voltage detection unit 49. The switches Swr, Swg, Swb, Swc, and Swa are, for example, n-type channel field effect transistors (FETs), and are switched between an on state (closed state) and an off state (open state) under the control of the second control unit 200. The switch section Swr is connected in series to the light source 11r. The switch section Swg is connected in series to the light source 11g. The switch section Swb is connected in series to the light source 11b. The switch section Swc and the capacitor C1 are connected in series to each other and are connected in parallel to the switch sections Swr, Swg, and Swb.

[0025] When the switch units Swr, Swg, and Swb are switched to the on state, they pass current from the light source driver 300 to the corresponding light sources 11r, 11g, and 11b, turning on the corresponding light sources 11r, 11g, and 11b. When the switch units Swr, Swg, and Swb are switched to the off state, they cut off the current from the light source driver 300 to the corresponding light sources 11r, 11g, and 11b, turning off the corresponding light sources 11r, 11g, and 11b. The switch unit Swa has a function of controlling the inductor current flowing from the light source driver 300 to the inductor L1 to a target value by switching to an on state. The switch section Swc has a function of adjusting the gradient of the rising portion of a pulse P (see FIG. 19) described later by passing a current from the light source driver 300 to the capacitor C1 when it is switched to an on state. The voltage detection unit 49 is connected between the ground and the switches Swr, Swg, Swb, Swc, and Swa, and outputs a voltage detection signal SV to the second control unit 200 after detecting it.

[0026] 5, the first control unit 100 is made up of a microcontroller equipped with a CPU (Central Processing Unit), a memory, etc., and controls the concave mirror driving unit 65. A required luminance signal SL indicating the light intensity of external light around the vehicle 2 detected through the illuminance sensor 7 is input to the first control unit 100. The first control unit 100 outputs the required luminance signal SL indicating the input required luminance to the second control unit 200.

[0027] The second control unit 200 is a large scale integration (LSI) that realizes desired functions by hardware, and is configured, for example, by an application specific integrated circuit (ASIC) or a field programmable gate array (FPGA). The second control unit 200 receives as input a video signal SE for displaying an image M from a video signal input unit 700, a light source temperature signal ST detected by a light source temperature detection unit 600, a voltage detection signal SV detected by a voltage detection unit 49, and a light intensity detection signal SFB detected by a light intensity detection unit 500.

[0028] The second control unit 200 includes a light source control unit 201 that sets the light intensity of the illumination light C according to a required luminance, a display element control unit 202 that controls the DMD display element 30, a storage unit 203 that stores illumination control data Dm, and a product data generation unit 205 that corrects the illumination control data Dm. The product data generation unit 205 includes a drive capability determination unit 205a, a master data selection unit 205b, a measurement point identification unit 205c, an output characteristic acquisition unit 205d, and a data correction unit 205e. The display element control unit 202 displays an image M by controlling the on / off of each micromirror 30a in the DMD display element 30 based on the video signal SE.

[0029] As shown in FIG. 13, the illumination control data Dm includes data indicating a luminance range Bl in each of the control modes Q1 to Qn (n is an arbitrary natural number). The luminance range Bl of each of the control modes Q1 to Qn is a luminance range for emitting illumination light C of a desired color, for example, white color, from the projector device 18. The median value of the luminance range Bl of the control modes Q1 to Qn becomes smaller as the control mode approaches from the control mode Q1 to the control mode Qn. Each of the control modes Q1 to Qn includes information on whether the control mode is a low luminance mode or a high luminance mode, a gain set by a gain setting unit 201a described later, a target value (limit value) of a current supplied to the light sources 11r, 11g, and 11b, a lighting pattern including a duty ratio of the light sources 11r, 11g, and 11b, an RGB output characteristic described later, and the like. For example, the gain and the target value are set smaller as the control mode approaches from the control mode Q1 to the control mode Qn. For example, when the mode is switched between the control mode Qx and the control mode Qy, the mode is switched between the low brightness mode and the high brightness mode. The lighting control data Dm is set for each light source temperature. As an example, lighting control data Dm is prepared for each of -40°C, -30°C, -10°C, 10°C, 25°C, 40°C, 50°C, 60°C, and 70°C. The lighting control data Dm differs for each light source temperature in the number and contents of the control modes Q1 to Qn, and the luminance range Bl for each control mode Q1 to Qn.

[0030] As shown in FIG. 5, the light source control unit 201 includes, for example, a PMIC (Power Management Integrated Circuit) that controls the power supplied to the light source group 11. The light source control unit 201 refers to illumination control data Dm related to a temperature closest to the light source temperature based on a light source temperature signal ST detected by a light source temperature detection unit 600. The light source control unit 201 refers to the illumination control data Dm, transitions to a control mode Q1 to Qn that realizes a requested luminance based on a requested luminance signal SL, and supplies a current to the light source group 11 via the light source driver 300 in the transitioned control mode Q1 to Qn. As a result, the illumination light C has a luminance according to the requested luminance signal SL. The output level of the light source control unit 201 is variable. As the output level of the light source control unit 201 increases, the peak value Pk (see FIG. 18 and FIG. 19) of the light source current increases, and the time until the light source current reaches a target value decreases, that is, the slope of the increase in the light source current increases.

[0031] For example, the light source control unit 201 determines a target value based on the requested luminance signal SL, and compares the determined target value with the light intensity detection signal SFB. The light source control unit 201 supplies a current from the light source driver 300 to the light source group 11 when the light intensity detection signal SFB is less than the target value, and stops the supply of current from the light source driver 300 to the light source group 11 when the light intensity detection signal SFB is equal to or greater than the target value. In this way, the light source control unit 201 monitors the light intensity detection signal SFB and feedback controls the current value supplied from the light source driver 300 to the light source group 11 with the target value as a target. This target value is set to a different value for each of the light sources 11r, 11g, and 11b.

[0032] As shown in FIG. 5, the light source control unit 201 includes a gain setting unit 201a that sets the gain of the light intensity detection signal SFB detected by the light intensity detection unit 500. The gain setting unit 201a sets the gain higher as the required luminance (required luminance signal SL) becomes lower. The gain setting unit 201a adjusts the gain of the light intensity detection signal SFB to a value that can be read by the light source control unit 201. The light source control unit 201 reads the light intensity detection signal SFB taking into account the presence or absence of a deviation in the gain set by the gain setting unit 201a and the amount of deviation. Thus, the luminance of the illumination light C is prevented from deviating from the target value due to the variation in gain caused by the individual difference of the light source control unit 201.

[0033] As shown in FIG. 18, the light source control unit 201 turns on the switch unit Swr for a light-on permission period Tr, whereby a current Ir is supplied from the light source driver 300 to the light source 11r, thereby turning on the light source 11r. The light source control unit 201 turns on the switch unit Swg for the light-on permission period Tg, whereby a current Ig is supplied from the light source driver 300 to the light source 11g, thereby turning on the light source 11g. The light source control unit 201 turns on the switch unit Swb for the light-on permission period Tb, whereby a current Ib is supplied from the light source driver 300 to the light source 11b, thereby turning on the light source 11b.

[0034] The light source control unit 201 selectively lights up one of the light sources 11r, 11g, and 11b, and switches the light sources 11r, 11g, and 11b to be turned on, in a so-called field sequential manner. The light source control unit 201 supplies currents Ir, Ig, and Ib to the light sources 11r, 11g, and 11b during the display period Ton, and stops the supply of currents Ir, Ig, and Ib to the light sources 11r, 11g, and 11b by turning off the switch units Swr, Swg, and Swb during the non-display period Tof. During the period in which the image M is displayed, the display period Ton and the non-display period Tof are repeated alternately. One display period Ton and one non-display period Tof constitute one frame, that is, one cycle. The display period Ton is composed of a plurality of light-permitted periods Tr, Tg, and Tb in a preset order.

[0035] The second control unit 200 switches to either a high brightness mode or a low brightness mode based on the requested brightness signal SL. The second control unit 200 switches to the low brightness mode when the requested brightness signal SL is equal to or less than a threshold, and switches to the high brightness mode when the requested brightness signal SL exceeds the threshold. For example, the threshold is set to 4000 candelas. In the high luminance mode, the second control unit 200 supplies the currents Ir, Ig, and Ib as rectangular waves to the light sources 11r, 11g, and 11b as shown in Fig. 18. In the high luminance mode, the second control unit 200 adjusts the luminance of the illumination light C or the display light L by changing the target value Tgt of the currents Ir, Ig, and Ib, the period Ti during which the currents Ir, Ig, and Ib are supplied, and a DMD duty ratio, which will be described later, in response to a change in the required luminance.

[0036] In the low luminance mode, the second control unit 200 supplies currents Ir, Ig, and Ib to the light sources 11r, 11g, and 11b as a plurality of pulses P, which are triangular waves, as shown in Fig. 19. In the low luminance mode, the second control unit 200 adjusts the luminance of the illumination light C or the display light L by increasing or decreasing the number of pulses P in response to a change in the required luminance. In addition, without being limited to this example, the second control unit 200 may adjust the brightness of the illumination light C or the display light L by increasing or decreasing the peak value Pk (target value) of the pulses P in addition to increasing or decreasing the number of pulses P.

[0037] A method for generating the pulse P in the low brightness mode will be described. As shown in FIG. 5 and FIG. 19, the second control unit 200 (light source control unit 201) turns on the switch units Swr and Swc and turns off the switch units Swg, Swb, and Swa before generating the pulse P during the lighting permission period Tr. At this time, a current flows from the light source driver 300 to the ground via the capacitor C1 and the switch unit Swc. As a result, energy is charged in the capacitor C1. When the capacitor C1 approaches a fully charged state, the current value flowing through the capacitor C1 decreases, and the current Ir supplied to the light source 11r via the switch unit Swr increases. As a result, the waveform of the rising part of the pulse P is formed. The inclination of the rising part of the pulse P can be adjusted by the capacitor C1. Then, when the current Ir reaches the target value Tgt, the second control unit 200 turns on the switch unit Swa. At this time, the current from the light source driver 300 flows to the ground via the switch unit Swa, and the current Ir supplied to the light source 11r decreases. As a result, the waveform of the falling part of the pulse P is formed.

[0038] 6, the lighting control data generating device 800 generates lighting control data Dm suitable for a shipped projector device 18k which is a shipped product of the projector device 18. The lighting control data generating device 800 includes a sample product data acquiring device 801 which acquires RGB output characteristics at each temperature in sample projector devices 18a to 18j which are samples of the projector device 18, a master data generating unit 802 which generates master data M1 to M10 which are master lighting control data based on the RGB output characteristics acquired through the sample product data acquiring device 801, a shipped product data acquiring device 810 which acquires the RGB output characteristics at each temperature in the shipped product projector device 18k, and a product data generating unit 205 which selects optimal master data Mx suitable for the shipped product projector device 18k from the master data M1 to M10, corrects the optimal master data Mx based on the RGB output characteristics acquired through the shipped product data acquiring device 810, and generates lighting control data Dm. The product data generating unit 205 constitutes a part of the shipment projector device 18k. The sample product data acquiring device 801, the master data generating unit 802, and the shipment data acquiring device 810 are provided separately from the projector device 18.

[0039] As shown in FIG. 7, the sample data acquisition device 801 includes a light meter 803 , a variable ND (Neutral Density) filter device 804 , a room temperature adjustment unit 806 , a thermostatic chamber 808 , and an inspection light emission unit 809 . The thermostatic chamber 808 is a container that keeps the temperature of the internal space constant. The room temperature adjustment unit 806 adjusts the temperature of the internal space of the thermostatic chamber 808 under the control of the master data generation unit 802. Any of the sample projector devices 18a to 18j are accommodated in the thermostatic chamber 808 in order. The thermostatic chamber 808 includes a thermostatic chamber glass 805 that transmits the display light L from the projector device 18. The thermostatic chamber glass 805 reduces the light intensity of the display light L when the display light L transmits therethrough. The inside of the thermostatic chamber 808 is a dark room. The light meter 803 and the variable ND filter device 804 are located in a darkroom outside the thermostatic chamber 808 . The light meter 803 measures the luminance of the display light L that has passed through the variable ND filter device 804, and outputs the measured detection signal to the master data generating unit 802. The inspection light emitting unit 809 irradiates the light intensity detecting unit 500 with inspection light for inspecting the presence or absence and amount of deviation of the gain set by the gain setting unit 201a.

[0040] The variable ND filter device 804 adjusts the luminance of the display light L that has passed through the thermostatic chamber glass 805 to within the measurable range of the light meter 803 under the control of the master data generating unit 802 . In detail, as shown in FIG. 20, the variable ND filter device 804 comprises a plurality of filters (five in this example) F0 to F4, each set to a different light attenuation rate, a rotating plate 804a supporting the filters F0 to F4, and a rotation drive unit 804c rotating the rotating plate 804a in a rotation direction Cw. The magnitude relationship of the optical attenuation rates of the filters F0 to F4 is set as follows: optical attenuation rate of filter F0>optical attenuation rate of filter F1>optical attenuation rate of filter F2>optical attenuation rate of filter F3>optical attenuation rate of filter F4. The rotating plate 804a is formed in a disk shape and is supported rotatably in a rotation direction Cw around a rotation axis Ay. The rotation direction Cw is a counterclockwise direction. The rotating plate 804a is configured to be rotatable only in one direction of the rotation direction Cw and not rotatable in the clockwise direction, which is the opposite direction of the rotation direction Cw. The rotation axis Ay is located at the center of the rotating plate 804a and extends along the thickness direction of the rotating plate 804a (the direction perpendicular to the paper surface of FIG. 20). The rotating plate 804a supports filters F0 to F4 aligned along the rotation direction Cw. The filters F0 to F4 are arranged at equal angular intervals around the rotation axis Ay, at intervals of 72° in this example. In the above, the rotating plate 804a is configured to be rotatable only in the counterclockwise direction, but the present invention is not limited to this and the rotating plate 804a may be configured to be rotatable only in the clockwise direction. The rotation driver 804c rotates the rotary plate 804a in a rotation direction Cw under the control of the master data generator 802, thereby causing an illumination range 804b, onto which the display light L is illuminated from the sample projector devices 18a to 18j, to overlap with one of the filters F0 to F4. The illumination range 804b is fixed with respect to the rotating rotary plate 804a. A method of switching the filters F0 to F4 when acquiring specific RGB output characteristics will be described in detail later.

[0041] 7, the master data generating unit 802 is, for example, a microcontroller. The master data generating unit 802 executes a master data generating process described later. The master data generating unit 802 includes a storage unit 807 that stores master data M1 to M10, a measurement point identifying unit 802a, and an output characteristic acquiring unit 802b. The process contents executed by the measurement point identifying unit 802a and the output characteristic acquiring unit 802b will be described in detail later.

[0042] As shown in FIG. 8, the shipment data acquisition device 810 includes a light meter 813 , a variable ND filter device 814 , a chamber 818 , and an inspection light emitting unit 819 . The chamber 818 is provided on the line where the shipped projector device 18k is installed, and houses the light meter 813 and the shipped projector device 18k. The inside of the chamber 818 is a dark room. Similar to the variable ND filter device 804, the variable ND filter device 814 includes a plurality of filters, a rotating plate that supports the plurality of filters, and a rotation drive unit that rotates the rotating plate in a rotational direction. The variable ND filter device 814 is controlled by the product data generation unit 205. The light meter 813 has a similar configuration to the light meter 803, and outputs a detection signal to the product data generation unit 205. The inspection light emission unit 819 has a similar configuration to the inspection light emission unit 809, and is controlled by the product data generation unit 205 to emit inspection light to the light intensity detection unit of the shipped projector device 18k.

[0043] (Master data generation process) The master data generation process executed by the master data generation unit 802 will be described with reference to the flowchart of FIG. First, as shown in FIG. 9, the master data generating unit 802 classifies the sample projector devices 18a to 18j into grades G1 to G10 according to the drive capability of the light source driver 300 (step S1). The sample projector devices 18a to 18j are the same type, but have different serial numbers. Therefore, the sample projector devices 18a to 18j have individual differences. The drive capability of the light source driver 300, which is one type of individual difference, is determined by the relationship between the output level of the light source control unit 201 and the peak value Pk of the light source current flowing through the light sources 11r, 11g, and 11b (see FIG. 18 and FIG. 19). The higher the drive capability of the light source driver 300, the larger the peak value Pk of the light source current flowing through the light sources 11r, 11g, and 11b becomes, even if the output level of the light source control unit 201 is low. The drive capability varies due to the individual difference of the light source driver 300. For example, if the drive capability of light source control unit 201 of sample projector device 18b is higher than that of light source control unit 201 of sample projector device 18a, even if the output levels of sample projector device 18a, 18b are the same, the peak value Pk of the light source current in sample projector device 18b will be higher than the peak value Pk of the light source current in sample projector device 18a, and this will also increase the brightness of the illumination light C or display light L. As an example, in step S1, master data generating unit 802 calculates a drive capability value for each of sample projector devices 18a to 18j by dividing peak value Pk of the light source current by the set output level. That is, the drive capability value is calculated by the following formula. Drive capacity value = Peak value Pk / output level Then, master data generating unit 802 sorts the calculated drive capability values ​​in descending order, and classifies sample projector devices 18a-18j into grades G1-G10 in descending order of drive capability value. For example, if sample projector device 18a has the lowest drive capability value among sample projector devices 18a-18j, sample projector device 18a is classified into grade G1. If sample projector device 18b has the second lowest drive capability value among sample projector devices 18a-18j, sample projector device 18b is classified into grade G2. Similarly, projector devices 18c-18j are classified into grades G3-G10, respectively.

[0044] Next, master data generating unit 802 generates master data M1 to M10 for each of grades G1 to G10, stores the generated master data M1 to M10 in storage unit 807 (step S2), and ends the master data generating process. The master data generating process is executed before manufacturing of shipment product projector device 18k. In step S2, the master data generating unit 802 reads out a sub-flowchart shown in FIG. 16 for generating the master data M1 to M10.

[0045] The process according to the sub-flowchart of FIG. 16 is executed for each of sample projector apparatus 18a-18j. As a result, master data M1-M10 corresponding to grades G1-G10 are generated. Each of master data M1-M10 has master data at each temperature. In the following example, a case where master data M1 of grade G1 is generated will be described. In this case, before the start of the sub-flowchart of FIG. 16, sample projector apparatus 18a belonging to grade G1 is placed in thermostatic chamber 808 shown in FIG. 7, and sample projector apparatus 18a is powered on.

[0046] First, the master data generating unit 802 sets the temperature in the thermostatic chamber 808 to a target temperature via the room temperature adjusting unit 806 (step S11). Then, the master data generating unit 802 waits for the temperature in the thermostatic chamber 808 to stabilize at the target temperature (step S12; NO). Then, when the master data generating unit 802 determines that the temperature in the thermostatic chamber 808 has stabilized at the target temperature (step S12; YES), it acquires gain deviation information, which is the IC characteristic of the light source control unit 201 (step S13). In this step S13, the master data generating unit 802 irradiates the light intensity detecting unit 500 with the inspection light via the inspection light emitting unit 809. The inspection light is light with a preset brightness. Then, the master data generating unit 802 measures the light intensity detection signal SFB when the inspection light is irradiated to the light intensity detecting unit 500 in a state where the gain is set to a set value by the gain setting unit 201a. Then, the master data generating unit 802 obtains gain deviation information indicating a deviation from the set value of the gain based on the difference between the measured light intensity detection signal SFB and the reference value. This reference value is, for example, an average value of the light intensity detection signal SFB when the light intensity detecting unit 500 is irradiated with the test light in a state where the gain is set to a set value by the gain setting unit 201a in the multiple projector devices 18.

[0047] Next, the master data generation unit 802 generates master data M1 by acquiring RGB output characteristics of each of the control modes Q1 to Qn at the target temperature adjusted by the room temperature adjustment unit 806, taking into account the acquired gain deviation information (step S14). 10, the RGB output characteristics are characteristics that indicate the relationship between the output level of the light source control unit 201 and the luminance of the display light L detected by the light meter 803. The RGB output characteristics include an R output characteristic associated with the light source 11r for emitting illumination light C of a desired color, for example, white, a G output characteristic associated with the light source 11g, and a B output characteristic associated with the light source 11b. This step S14 includes a measurement point identification step S14a executed by a measurement point identification unit 802a which identifies a plurality of measurement points P1 to Px based on each of a plurality of different output levels of the light source control unit 201 and the luminance of the light emitted by the light sources 11r, 11g, and 11b, and an output characteristic acquisition step S14b executed by an output characteristic acquisition unit 802b which acquires RGB output characteristics by interpolating between the identified plurality of measurement points P1 to Px. The x of the measurement point Px shown in Fig. 10 is an arbitrary number, and in the master data, x is set to the same number, for example, 20, in both the low brightness mode and the high brightness mode. High reliability is required for the master data. For this reason, the number of measurement points in the master data is set to be greater than the number of measurement points when acquiring the RGB output characteristics of the shipped projector device 18k described later. In detail, the measurement point specifying unit 802a sequentially measures the red light from the light source 11r, the green light from the light source 11g, and the blue light from the light source 11b. For example, when measuring the red light, the measurement point specifying unit 802a sets the output level of the light source control unit 201 to a first value, and sequentially lights up the light sources 11r, 11g, and 11b by supplying currents Ir, Ig, and Ib to the light sources 11r, 11g, and 11b as shown in Fig. 18. When measuring the red light, the measurement point specifying unit 802a turns on each micromirror 30a of the DMD display element 30 during a period when the light source 11r, which is the light source to be measured, is turned on, and turns off each micromirror 30a of the DMD display element 30 during a period when the light sources 11g and 11b other than the light source 11r are turned on. Then, the measurement point specifying unit 802a measures the luminance of red light, which is the display light L, through the light meter 803, and plots it at a measurement point P1 where the first value and the luminance of the red light intersect. Next, the measurement point specifying unit 802a sets the output level of the light source control unit 201 to a second value greater than the first value, measures the luminance of the red light, which is the display light L, through the light meter 803 in the same manner as above, and plots the result at measurement point P2 where the second value and the luminance of the red light intersect. Thereafter, measurement points P3 to Px are plotted in the same manner. Measurement points P1 to Px shown in FIG. 10 are set at equal intervals on the horizontal axis corresponding to the output level of the light source control unit 201.

[0048] In either the low brightness mode or the high brightness mode, the measurement point identification unit 802a measures the luminance of the red light of the light source 11r for a preset number of measurements (e.g., 10 times) at the output level of the light source control unit 201, and identifies the measurement points P1 to Px by averaging the luminance for the number of measurements. High reliability is required for the master data. For this reason, the number of averaging of the luminance when generating the master data is set to be greater than the number of averaging of the luminance when generating the illumination control data Dm of the shipped projector device 18k described later.

[0049] The output characteristic acquisition unit 802b acquires the R output characteristic of the light source 11r indicated by the broken line Lr in FIG. 10 by performing interpolation, for example, linear interpolation, between the identified measurement points P1 to Px. As with the R output characteristic, the master data generating unit 802 acquires the G output characteristic related to the light source 11g shown by the broken line Lg in Fig. 10 and the B output characteristic related to the light source 11b shown by the broken line Lb in Fig. 10. When specifying the measurement point of the G output characteristic, the master data generating unit 802 turns on each micromirror 30a of the DMD display element 30 during the period when the light source 11g, which is the light source to be measured, is turned on, and turns off each micromirror 30a of the DMD display element 30 during the period when the light sources 11r and 11b other than the light source 11g are turned on. When specifying the measurement point of the B output characteristic, the master data generating unit 802 turns on each micromirror 30a of the DMD display element 30 during the period when the light source 11b, which is the light source to be measured, is turned on, and turns off each micromirror 30a of the DMD display element 30 during the period when the light sources 11r and 11g other than the light source 11b are turned on. In this way, the RGB output characteristics are acquired. The master data generating unit 802 acquires the RGB output characteristics for each of the control modes Q1 to Qn.

[0050] For example, if the gain is deviated so as to exceed the set value, if the correction that takes into account the gain deviation information is not performed, the current value of the light intensity detection signal SFB relative to the light intensity of the light irradiated to the light intensity detection unit 500 will be high, and the luminance of the display light L adjusted based on the light intensity detection signal SFB will also be high. In this way, in order to suppress the luminance of the display light L from increasing as the gain exceeds the set value, the correction that takes into account the gain deviation information is performed. For example, when the gain deviation information includes information that the gain is deviated so as to exceed the set value, the master data generation unit 802 corrects the measurement points P1 to Px and the broken lines Lr, Lg, and Lb to be shifted downward, i.e., in the direction of decreasing luminance, by taking into account the acquired gain deviation information. Similarly, when the gain deviation information includes information that the gain is deviated so as to be below the set value, the master data generation unit 802 corrects the measurement points P1 to Px and the broken lines Lr, Lg, and Lb to be shifted upward, i.e., in the direction of increasing luminance, by taking into account the acquired gain deviation information. The amount of correction at this time is a value according to the amount of deviation between the gain and the set value included in the gain deviation information.

[0051] In the measurement point identification step S14a, when the measurement point identification unit 802a detects the brightness of light from the light sources 11r, 11g, and 11b through the light meter 803, it sets one of the filters F0 to F4 as the selected filter Fs by superimposing the filter F0 to F4 on the irradiation range 804b through the variable ND filter device 804, as shown in Table 1 below.

[0052] [Table 1]

[0053] As shown in Table 1 above, the variable ND filter device 804 acquires RGB output characteristics in descending order of the median value of the luminance range Bl from control mode Q1 to control mode Qn under the control of the master data generation unit 802. At this time, the variable ND filter device 804 switches the selection filter Fs in the order of filter F0 → filter F1 → filter F2 → filter F3 → filter F4, in other words, switches filters F0 to F4 in descending order of the light attenuation rate. In Table 1 above, a, b, c, and d of control modes Qa, Qb, Qc, and Qd are arbitrary numbers and are set in the magnitude relationship of 2 < a < b < c < d < n.

[0054] Specifically, as shown in Table 1 above, when the variable ND filter device 804 acquires the R output characteristic, G output characteristic, and B output characteristic of control mode Q1, it sets filter F0 as the selection filter Fs. After the variable ND filter device 804 acquires the B output characteristic of control mode Q1 and before starting to acquire the R output characteristic of control mode Q2, it switches the selection filter Fs from filter F0 to filter F1. At this time, as shown in FIG. 20, the variable ND filter device 804 rotates the rotating plate 804a by a switching angle α along the rotation direction Cw via the rotation drive unit 804c. This switching angle α is set to the angle obtained by dividing 360° by the number of filters.

[0055] Then, as shown in Table 1 above, the variable ND filter device 804 maintains the selection filter Fs as filter F1 from control mode Q2 to control mode Qa. Next, after the variable ND filter device 804 acquires the B output characteristic of control mode Qa and before acquiring the R output characteristic of control mode Qb, it switches the selection filter Fs from filter F1 to filter F2. At this time, as shown in FIG. 20, the variable ND filter device 804 rotates the rotating plate 804a by a switching angle α along the rotation direction Cw via the rotation drive unit 804c.

[0056] The variable ND filter device 804 maintains the selected filter Fs at filter F2 from control mode Qb to control mode Qc, as shown in Table 1 above. Next, after acquiring the B output characteristics of control mode Qc, the variable ND filter device 804 switches the selected filter Fs from filter F2 to filter F3 before acquiring the R output characteristics of control mode Qd. At this time, the variable ND filter device 804 rotates the rotating plate 804a by a switching angle α along the rotation direction Cw via the rotary drive unit 804c, as shown in FIG.

[0057] The variable ND filter device 804 maintains the selected filter Fs at filter F3 from control mode Qd to control mode Qn-1, as shown in Table 1 above. Next, after acquiring the B output characteristics of control mode Qn-1, the variable ND filter device 804 switches the selected filter Fs from filter F3 to filter F4 before acquiring the R output characteristics of control mode Qn. At this time, the variable ND filter device 804 rotates the rotating plate 804a by the switching angle α along the rotation direction Cw via the rotary drive unit 804c. In this manner, the RGB output characteristics in the control modes Q1 to Qn are acquired. When the RGB output characteristics are acquired in the control modes Q1 to Qn, the selection filter Fs is not switched so that the light attenuation rate is reduced. For example, when the selection filter Fs is switched from the filter F2 to the filter F1 so that the light attenuation rate is reduced, it is necessary to rotate the rotating plate 804a along the rotation direction Cw through an angle larger than the switching angle α, for example, 288°. In this case, it takes time to switch the selection filter Fs. On the other hand, in this embodiment, when switching the selection filter Fs, it is only necessary to rotate the rotating plate 804a by the switching angle α, so that the time required for switching the selection filter Fs is suppressed.

[0058] In this example, the variable ND filter device 804 sets a common selection filter Fs for each of the control modes Q1 to Qn, but this is not limited to the above. For example, after acquiring the R output characteristic of the control mode Qa, the variable ND filter device 804 may switch the selection filter Fs from filter F1 to filter F2 before acquiring the G output characteristic of the control mode Qa.

[0059] The master data generation unit 802 determines whether or not the master data M1 has been generated at each temperature (step S15). The respective temperatures are, for example, -40°C, -30°C, -10°C, 10°C, 25°C, 40°C, 50°C, 60°C, and 70°C. When the master data generation unit 802 determines that the master data M1 has not been generated at each temperature (step S15; NO), the process returns to step S11, and the target temperature is set via the room temperature adjustment unit 806 to a temperature at which the master data M1 has not been generated. That is, the processes of steps S11 to S15 are repeated, and the master data M1 is generated at each temperature.

[0060] When the master data generation unit 802 determines that the master data M1 has been generated for each temperature (step S15; YES), it stores the generated master data M1 for each temperature in the storage unit 807 (step S16), and the sub-flowchart of Fig. 16 ends. The master data M1 includes the same content as the illumination control data Dm shown in Fig. 13 described above. The master data M2 to M10 are also generated by the sub-flowchart of Fig. 16, like the master data M1.

[0061] (Product data generation process) Next, the product data generation process executed by the product data generation unit 205 will be described with reference to the flowchart of FIG. First, the drive capability determining unit 205a determines the drive capability of the light source driver 300 of the shipped projector device 18k (step S21). In this step S21, for example, the drive capability determining unit 205a calculates the drive capability value of the light source driver 300 of the shipped projector device 18k as described above. Then, master data selection unit 205b selects optimum master data Mx from master data M1-M10 based on the determined drive capability (step S22). In this step S22, master data selection unit 205b selects, as optimum master data Mx, the master data corresponding to the group to which the sample projector device that is closest to the calculated drive capability value belongs among the drive capability values ​​of each of sample projector devices 18a-18j. Then, the product data generating unit 205 stores the selected optimum master data Mx as temporary lighting control data Dm in the storage unit 203 (step S23). In steps S24 to S26, the shipped projector device 18k operates based on the temporary lighting control data Dm.

[0062] Next, the output characteristic acquisition unit 205d acquires gain deviation information of the shipped projector device 18k through the shipment data acquisition device 810 (step S24), and acquires RGB output characteristics at room temperature in the shipped projector device 18k by taking into account the acquired gain deviation information (step S25). Steps S24 and S25 are the same processes as steps S13 and S14, respectively. The process of step S25 only acquires RGB output characteristics at room temperature, and therefore can be performed in a short time compared to the master data generation process that acquires RGB output characteristics at each temperature.

[0063] This step S25, similar to the step of acquiring the RGB output characteristics of the master data relating to step S14 above, includes a measurement point identification step S25a executed by the measurement point identification unit 205c which identifies a plurality of measurement points P1 to Pm, Pn based on the luminance of the light emitted by the light sources 11r, 11g, 11b at each of a plurality of different output levels in the light source control unit 201, and an output characteristic acquisition step S25b executed by the output characteristic acquisition unit 205d which acquires the RGB output characteristics by interpolating between the identified plurality of measurement points P1 to Pm, Pn.

[0064] The following describes step S25, which acquires the RGB output characteristics of the shipped product, focusing on the differences from step S14, which acquires the RGB output characteristics related to the master data. Note that the scale of the vertical axis indicating the luminance is different in the graphs of Fig. 11 and Fig. 12, but the reference value Sp set on the vertical axis is set to the same value. The reference value Sp is, for example, 2000 Nit. In the high luminance mode in which the required luminance exceeds the threshold, the measurement point specifying unit 205c specifies a first specified number n of measurement points P1 to Pn as shown in Fig. 11. In the high luminance mode, the output characteristic acquisition step S25b acquires the RGB output characteristics by linearly interpolating between the specified measurement points P1 to Pn.

[0065] In a low brightness mode in which the required brightness is equal to or lower than a threshold value, the measurement point specifying unit 205c specifies a second specified number m of measurement points P1 to Pm as shown in Fig. 12. In the low brightness mode, the output characteristic acquisition step S25b acquires the RGB output characteristics by linearly interpolating between the specified measurement points P1 to Pm. In the low brightness mode, the output characteristic acquisition unit 205d may perform curved interpolation instead of linear interpolation between the specified measurement points P1 to Pm. Curved interpolation is, for example, Lagrange interpolation, spline interpolation, or least squares method. In the high brightness mode, the relationship between the brightness and the output level of the light source control unit 201 changes linearly, while in the low brightness mode, the relationship between the brightness and the output level of the light source control unit 201 tends to change curvedly. Taking this tendency into consideration, it is preferable to perform curved interpolation between the measurement points P1 to Pm in the low brightness mode. The first specific number of points n and the second specific number of points m are each a natural number, and the second specific number of points m is greater than the first specific number of points n, i.e., there is a magnitude relationship of m>n. In this way, the second specific number of points m in the low brightness mode is set to be greater than the first specific number of points n in the high brightness mode, thereby improving the reliability of the RGB output characteristics in the low brightness mode, which requires higher accuracy than the high brightness mode. In this example, the first specific number of points n is 10, and the second specific number of points m is 15. The measurement points P1 to Pn and the measurement points P1 to Pm are set at equal intervals on the horizontal axis corresponding to the output level of the light source control unit 201. Note that, like the measurement point specifying unit 802a, the measurement point specifying unit 205c turns on each micromirror 30a of the DMD display element 30 during a period when any one of the light sources 11r, 11g, and 11b that is the measurement target light source is turned on, and turns off each micromirror 30a of the DMD display element 30 during a period when a light source other than the measurement target light source among the light sources 11r, 11g, and 11b is turned on. For example, when acquiring the RGB output characteristics of the control mode Q1, the light sources other than the measurement target light source are turned on at the median luminance of the luminance range Bl1 of the control mode Q1.

[0066] In the low luminance mode, the measurement point specifying unit 205c measures the luminance of the light of the light source to be measured over a second measurement count N2 at the output level set by the light source control unit 201, and specifies the measurement points P1 to Pm by averaging the luminance for the number of measurements. In the high luminance mode, the measurement point specifying unit 205c measures the luminance of the light of the light source to be measured over a first measurement count N1 at the output level set by the light source control unit 201, and specifies the measurement points P1 to Pn by averaging the luminance for the number of measurements. In the low luminance mode, the measurement points P1 to Pm with higher accuracy are obtained. Therefore, the second measurement count N2 is set to a number larger than the first measurement count N1. As an example, the second measurement count N2 is set to five times, and the first measurement count N1 is set to three times.

[0067] Then, the product data generating unit 205 acquires the comparison data Mc shown in Fig. 13 based on the acquired RGB output characteristics (step S26). The comparison data Mc is data to be compared with the optimal master data Mx, and the luminance range Bl in each of the control modes Q1 to Qn is different from the optimal master data Mx.

[0068] Next, the data correcting unit 205e generates the illumination control data Dm by correcting the optimal master data Mx based on the difference between the comparison data Mc and the optimal master data Mx at room temperature (for example, 25° C.) (step S27). In step S27, the product data generating unit 205 obtains difference values ​​Df1 and Df2 between the luminance range Bl1 of the optimal master data Mx at room temperature and the luminance range Bl2 of the comparison data Mc in the control mode Q1, as shown in FIG. 14. The difference value Df1 is the difference value between the maximum values ​​of the luminance ranges Bl1 and Bl2. The difference value Df2 is the difference value between the minimum values ​​of the luminance ranges Bl1 and Bl2. Then, the product data generating unit 205 corrects the luminance range Bl of the optimal master data Mx in the control mode Q1 for each temperature using the difference values ​​Df1 and Df2 as correction values. For example, the product data generating unit 205 increases the upper limit value of the luminance range Bl1 of the optimal master data Mx by the difference value Df1, and increases the lower limit value of the luminance range Bl1 of the optimal master data Mx by the difference value Df2. The luminance range Bl is corrected in the same manner in the control modes Q2 to Qn. That is, the correction value based on the comparison between the optimum master data Mx at room temperature and the comparison data Mc is also used to correct the optimum master data Mx at each temperature other than room temperature, thereby simplifying the correction of the optimum master data Mx.

[0069] The product data generating unit 205 writes the corrected optimum master data Mx as the illumination control data Dm in the storage unit 203 (step S28), and ends the product data generating process. This allows the shipped projector device 18k to use the illumination control data Dm suitable for the shipped projector device 18k, so that the luminance and chromaticity of the display light L can be brought closer to the target values.

[0070] Next, the operation of the projector device 18, which is the shipped projector device 18k in which the illumination control data Dm has been written as described above, will be described. As shown in FIG. 13, the second control unit 200 of the projector device 18 switches between the control modes Q1 to Qn according to the required brightness. The ends of the brightness range Bl of the control modes Q1 to Qn are set to the non-use range J. The second control unit 200 switches between the control modes Q1 to Qn before the required brightness reaches the non-use range J. The non-use range J is a range of the brightness range Bl of the control modes Q1 to Qn that is not used by the projector device 18. The ends of the brightness range Bl have a lower accuracy in realizing a desired color, for example, white illumination light C or display light L, compared to the central part other than the ends of the brightness range Bl. Therefore, by setting the ends of the brightness range Bl of the control modes Q1 to Qn to the non-use range J, the accuracy in realizing a desired color, for example, white illumination light C or display light L, is improved.

[0071] Next, a method for setting the non-use range J will be described. The non-use range J may be set automatically by a program executed by the second control unit 200, or may be set by a human operation of a computer or the like. Below, with reference to Fig. 21, a non-use range J1 located at the lower end of the luminance range BlA of the control mode Q1 and a non-use range J2 located at the lower end of the luminance range BlB of the control mode Q2 will be described, but the non-use ranges J of the other control modes Q3 to Qn are set in a similar manner. As shown in Fig. 21, an overlapping area E1 where the luminance range BlA of control mode Q1 and the luminance range BlB of control mode Q2 overlap is identified. Then, a mode switching value E2 is set at a non-end of the overlapping area E1. The mode switching value E2 is set to, for example, the median value of the overlapping area E1. The non-use range J1 is set to a range of the luminance range BlA of control mode Q1 that is equal to or less than the mode switching value E2. The non-use range J2 is set to a range of the luminance range BlB of control mode Q2 that is equal to or more than the mode switching value E2.

[0072] When the second control unit 200 is controlling the light sources 11r, 11g, and 11b in the control mode Q1 and the requested luminance decreases and reaches the mode switching value E2, the control mode transitions from the control mode Q1 to the control mode Q2. When the second control unit 200 is controlling the light sources 11r, 11g, and 11b in the control mode Q2 and the requested luminance increases and reaches the mode switching value E2, the control mode transitions from the control mode Q2 to the control mode Q1.

[0073] The second control unit 200 turns on each micromirror 30a of the DMD display element 30 during the display period Ton and turns off each micromirror 30a of the DMD display element 30 during the non-display period Tof. The second control unit 200 can adjust the luminance of the display light L by the DMD duty ratio of the DMD display element 30. The DMD duty ratio is calculated as the ratio of the total time of the display period Ton to one period.

[0074] 22 and 23, in the high luminance mode, that is, in the control modes Q1 to Qx, the display period Ton is set in the first half of one cycle, and the non-display period Tof is set in the second half of one cycle. In the low luminance mode, that is, in the control modes Qy to Qn, the non-display period Tof is set at the beginning and end of one cycle, and the display period Ton is set to be sandwiched between the first and last display periods Ton.

[0075] As shown in Fig. 22, the second control unit 200 sets the DMD duty ratio to 85% in the control mode Q1, sets the DMD duty ratio to 75% in the control mode Q2, and sets the DMD duty ratio to 50% in the control modes Q3 to Qn. In this way, the DMD duty ratio in the control mode Q2 is set to a value between the DMD duty ratio in the control mode Q1 and the DMD duty ratio in the control mode Q3, for example, a median value between the DMD duty ratio in the control mode Q1 and the DMD duty ratio in the control mode Q3. This suppresses a sudden change in the DMD duty ratio when the mode is switched between the control modes Q1, Q2, and Q3, thereby suppressing a sudden change in the luminance of the display light L when the mode is switched between the control modes Q1 to Qn, and suppresses flickering of the virtual image V.

[0076] 23, when the control mode is switched from a control mode Qx belonging to a high luminance mode to a control mode Qy belonging to a low luminance mode, a non-display period Tof is set at the beginning of one cycle in the control mode Qy. This prevents the luminance of the display light L from increasing instantaneously when the control mode Qx is switched to the control mode Qy. 23, when the control mode Qy belonging to the low luminance mode is switched to the control mode Qx belonging to the high luminance mode, the display period Ton is set in the first half of one cycle in the control mode Qx. This prevents the luminance of the display light L from decreasing instantaneously when the control mode Qy is switched to the control mode Qx. In this example, the positions of the display period Ton and the non-display period Tof in one cycle are different between the control modes Q1 to Qx of the high luminance mode and the control modes Qy to Qn of the low luminance mode. However, the present invention is not limited to this, and the phases of the waveforms of the currents Ir, Ig, and Ib may be changed between the control modes Q1 to Qx of the high luminance mode and the control modes Qy to Qn of the low luminance mode to suppress an instantaneous change in the luminance of the display light L between the control modes Qy and Qx. Furthermore, the second control unit 200 supplies a plurality of rectangular waves of currents Ir, Ig, Ib, each having a different width (period Ti in FIG. 18), to the light sources 11r, 11g, 11b during the display period Ton. In this case, the second control unit 200 may place a rectangular wave with a longer width among the rectangular waves of currents Ir, Ig, Ib at the rear end portion of the display period Ton in either the high brightness mode or the low brightness mode.

[0077] Note that a part of the control contents of the first control unit 100 may be executed by the second control unit 200, and conversely, a part of the control contents of the second control unit 200 may be executed by the first control unit 100. Furthermore, the first and second control units 100 and 200 may be configured as a single control unit.

[0078] (effect) According to the embodiment described above, the following effects are achieved. (1-1) A lighting control data generating method for generating lighting control data Dm for controlling a plurality of light sources 11r, 11g, 11b in a HUD device 1 includes a measurement point specifying step S25a for specifying a plurality of measurement points P1-Pn, Pm according to the luminance of light emitted by the light sources 11r, 11g, 11b at each of a plurality of output levels that are set to different values ​​in a light source control unit 201 that controls the light sources 11r, 11g, 11b by referring to the provisional lighting control data Dm, and an output characteristic acquiring step S25b for generating lighting control data Dm by acquiring RGB output characteristics by interpolating between the specified plurality of measurement points P1-Pn, Pm. In the measurement point specifying step S25a, a first specific number n of measurement points P1-Pn are specified in a high luminance mode in which the required luminance exceeds a threshold, and a second specific number m of measurement points P1-Pm that is greater than the first specific number n are specified in a low luminance mode in which the required luminance is equal to or less than the threshold. According to this configuration, the number of measurement points P1 to Pn in the high brightness mode is set to be smaller than the number of measurement points P1 to Pm in the low brightness mode. Therefore, the process of identifying the measurement points P1 to Pn, Pm in the measurement point identification step S25a can be completed in a short time. Therefore, the time required to generate the illumination control data Dm can be shortened. In the high luminance mode, the relationship between the output level of the light source control unit 201 and the luminance changes linearly, so even if the number of measurement points P1 to Pn in the high luminance mode is reduced, there is little effect on the broken lines Lr, Lg, and Lb indicating the RGB output characteristics, and the reliability of the illumination control data Dm is ensured. On the other hand, in the low luminance mode, the relationship between the output level of the light source control unit 201 and the luminance changes curvilinearly, so from the viewpoint of ensuring the reliability of the illumination control data Dm, it is preferable to have a larger number of measurement points P1 to Pm in the low luminance mode.

[0079] (1-2) In the output characteristic acquisition step S25b, when the required brightness is in a high brightness mode where the threshold value is exceeded, linear interpolation is performed between the measurement points P1 to Pn of a first specific number n of points, and when the required brightness is in a low brightness mode where the threshold value is exceeded, curved interpolation is performed between the measurement points P1 to Pm of a second specific number m of points. According to this configuration, in the high brightness mode, the relationship between the output level of the light source control section 201 and the brightness changes linearly, so that the reliability of the illumination control data Dm is improved by linearly interpolating between the measurement points P1 to Pn. On the other hand, in the low luminance mode, the relationship between the output level of the light source control section 201 and the luminance changes in a curved manner, so that the reliability of the illumination control data Dm is improved by performing curved interpolation between the measurement points P1 to Pm.

[0080] (1-3) In the measurement point identification step S25a, in a high brightness mode in which the required brightness exceeds a threshold value, the brightness of light emitted by any one of the light sources 11r, 11g, and 11b is measured over a first measurement count N1 at the set output level of the light source control unit 201, and the measurement points P1 to Pn are identified by averaging the brightness measured over the first measurement count N1. In a low brightness mode in which the required brightness is equal to or less than the threshold value, the brightness of light emitted by any one of the light sources 11r, 11g, and 11b is measured over a second measurement count N2 that is greater than the first measurement count N1 at the set output level of the light source control unit 201, and the measurement points P1 to Pm are identified by averaging the brightness measured over the second measurement count N2. In the low luminance mode, compared to the high luminance mode, a slight change in luminance has a large effect on the visibility of the virtual image V. For this reason, by making the number of measurements in the low luminance mode greater than the number of measurements in the high luminance mode, the accuracy of the measurement points P1 to Pn in the low luminance mode can be improved, and the visibility of the virtual image V can be improved.

[0081] (1-4) The lighting control data Dm includes a plurality of control modes Q1 to Qn corresponding to required brightness. In the output characteristic acquisition step S25b, RGB output characteristics are acquired for each of the plurality of control modes Q1 to Qn. In the measurement point identification step S25a, one of the plurality of filters F0 to F4 having different light attenuation rates is used as the selection filter Fs to attenuate the brightness of the illumination light C or the display light L based on the light emitted by any of the light sources 11r, 11g, and 11b so that it falls within a measurable range by the light meter 803. When acquiring the RGB output characteristics in order from the control modes Q1 to Qn having the highest required brightness, the plurality of filters F0 to F4 are switched to the selection filter Fs in order of the highest light attenuation rate, that is, in the order of filter F0 → filter F1 → filter F2 → filter F3 → filter F4. According to this configuration, when acquiring the RGB output characteristics, the order of switching to the selected filter Fs among the filters F0 to F4 can be simplified. Therefore, the time required for switching the selected filter Fs can be shortened, and the luminance can be quickly measured by the light meter 803. Therefore, the time required for generating the illumination control data Dm can be shortened.

[0082] (1-5) In the measurement point identification step S25a, when identifying measurement points P1 to Pn, Pm related to the luminance of a specific target light (e.g., red light) emitted by a specific target light source (e.g., light source 11r) among the multiple light sources 11r, 11g, 11b, the multiple light sources 11r, 11g, 11b are turned on in sequence, while the specific target light from the specific target light source is reflected toward the transmissive screen 50 through the DMD display element 30, and light (e.g., green light and blue light) from light sources other than the specific target light source among the multiple light sources 11r, 11g, 11b (e.g., light sources 11g, 11b) is reflected toward a direction different from the transmissive screen 50. According to this configuration, by illuminating a light source other than the specific target light source, it is possible to measure the luminance of the specific target light in a state close to the actual use of the HUD device 1. Therefore, it is possible to identify the measurement points P1 to Pn, Pm with higher accuracy. For example, when measuring the luminance of a specific object light (e.g., red light) to identify the measurement points P1 to Pn, Pm, it is assumed that the chromaticity of the specific object light (red light) changes due to the influence of light of a color other than the specific object light (e.g., green light and blue light). According to the above configuration, it is possible to identify the measurement points P1 to Pn, Pm taking into account the influence of light of a color other than the specific object light.

[0083] (1-6) The lighting control data generating device 800 generates lighting control data Dm for controlling the light sources 11r, 11g, and 11b in the HUD device 1. The lighting control data generating device 800 includes a measurement point specifying unit 205c that specifies a plurality of measurement points P1 to Pn according to the luminance of light emitted by the light sources 11r, 11g, and 11b at each of a plurality of output levels that are set to different values ​​in a light source control unit 201 that controls the light sources 11r, 11g, and 11b by referring to the lighting control data Dm, and an output characteristic acquiring unit 205d that generates the lighting control data Dm by acquiring RGB output characteristics by interpolating between the specified plurality of measurement points P1 to Pn, Pm. The measurement point specifying unit 205c specifies a first specific number n of measurement points P1 to Pn when the high luminance mode is in a high luminance mode in which the required luminance exceeds a threshold, and specifies a second specific number m of measurement points P1 to Pm that is greater than the first specific number n when the low luminance mode is in a low luminance mode in which the required luminance is equal to or less than the threshold. According to this configuration, as described above, it is possible to shorten the time required to generate the illumination control data Dm.

[0084] (2-1) The HUD device 1 includes a plurality of light sources 11r, 11g, and 11b, a light source driver 300 that drives the light sources 11r, 11g, and 11b, a second control unit 200 that is an example of a control unit that turns on the plurality of light sources 11r, 11g, and 11b via the light source driver 300 based on illumination control data Dm, and a DMD display element 30 that generates display light L based on illumination light C emitted by the plurality of light sources 11r, 11g, and 11b. The illumination control data Dm includes a control mode Q1 that is an example of a first control mode for generating illumination light C with a luminance according to a requested luminance, and a control mode Q2 that is an example of a second control mode. The control modes Q1 and Q2 have different luminance ranges BlA and BlB that partially overlap each other. The second control unit 200 switches between the control modes Q1 and Q2 when the required brightness reaches a mode switching value E2 located at a non-edge of an overlapping area E1 where the brightness range BlA of the control mode Q1 and the brightness range BlB of the control mode Q2 overlap. The ends of the luminance range Bl of each of the control modes Q1 to Qn are regions with low accuracy in realizing a desired color, for example, white illumination light C. According to the above configuration, by setting the mode switching value E2 at a non-end of the overlapping region E1, the ends of the luminance ranges BlA and BlB of the control modes Q1 and Q2 are set to the non-use range J. Therefore, it is possible to change the luminance of the illumination light C according to the required luminance while realizing illumination light C of a desired color (for example, white). This improves the visibility of the virtual image V.

[0085] (2-2) The mode switching value E2 is set to the median value of the overlapping area E1. According to this configuration, for example, the non-use ranges J1, J2 of the two control modes Q1, Q2 can be set to the same length.

[0086] (2-3) The HUD device 1 includes a transmissive screen 50 that receives display light L from a DMD display element 30 and displays an image M. The DMD display element 30 includes a plurality of micromirrors 30a that are provided corresponding to pixels of the image M. Under the control of the second control unit 200, each micromirror 30a switches between an ON state in which light from the light sources 11r, 11g, and 11b is reflected toward the transmissive screen 50 and an OFF state in which light from the light sources 11r, 11g, and 11b is reflected in a direction different from the transmissive screen 50. The median value of the luminance range BlA of the control mode Q1 is set to be larger than the median value of the luminance range BlB of the control mode Q2 and the median value of the luminance range Bl of the control mode Q3, which is an example of the third control mode. The median value of the luminance range BlB of the control mode Q2 is set to be smaller than the median value of the luminance range BlA of the control mode Q1 and larger than the median value of the luminance range Bl of the control mode Q3. The second control unit 200 adjusts the brightness of the display light L by changing the DMD duty ratio, which is the period during which the micromirror 30a is in the ON state in one period. The DMD duty ratio of the control mode Q1 is set to be larger than the DMD duty ratio of the control mode Q2 and the DMD duty ratio of the control mode Q3. The DMD duty ratio of the control mode Q2 is set to be larger than the DMD duty ratio of the control mode Q3 and smaller than the DMD duty ratio of the control mode Q1. According to this configuration, when the control modes Q1, Q2, and Q3 are switched, the DMD duty ratio is prevented from changing suddenly. This prevents the luminance of the display light L from changing suddenly due to a change in the required luminance. This improves the visibility of the virtual image V.

[0087] The present disclosure is not limited to the above-described embodiments and drawings. Modifications (including deletion of components) can be made as appropriate within the scope of the present disclosure. An example of a modification will be described below.

[0088] (Modification) In the above embodiment, the correction value based on the comparison between the optimum master data Mx at room temperature and the comparison data Mc is also applied to the correction of the optimum master data Mx at temperatures other than room temperature. However, this is not limited to this, and the correction value for each temperature may be obtained and applied to the master data Mx at each temperature.

[0089] In the above embodiment, the output characteristic acquisition unit 205d acquires the RGB output characteristics at room temperature in the shipped projector device 18k taking into account the acquired gain deviation information, but it is not necessary to take into account the gain deviation information.

[0090] In the above embodiment, the HUD device 1 is for mounting on a vehicle, but it may be mounted on a vehicle such as an airplane, a ship, etc. Also, the display light L from the HUD device 1 is projected onto the windshield 3, but it may be projected onto a dedicated combiner.

[0091] In the above embodiment, the second control unit 200 transitions to either the high brightness mode or the low brightness mode based on the required brightness signal SL indicating the light intensity of external light. However, this is not limited to this, and the required brightness may be changed by the viewer 4 operating an operation unit (not shown) provided on the HUD device 1 or the vehicle 2, thereby transitioning between the above modes. The variable ND filter devices 804 and 814 in the above embodiments may be omitted.

[0092] In the above embodiment, the master data generation unit 802 sets the number of measurement points to be the same in both low brightness mode and high brightness mode, but this is not limited to the above, and similar to the product data generation unit 205, the number of measurement points in low brightness mode may be set to be greater than the number of measurement points in high brightness mode.

[0093] In the above embodiment, the mode switching value E2 is set to the median value of the overlap region E1, but it may be set to a value other than the median value of the overlap region E1 as long as it is within the overlap region E1.

[0094] In the above embodiment, the number of measurements in low brightness mode (second number of measurements N2) is set to a number greater than the number of measurements in high brightness mode (first number of measurements N1), but this is not limited to the above, and the number of measurements may be set to the same number between low brightness mode and high brightness mode. Also, the number of measurements is not limited to multiple times, and may be a single number. When the number of measurements is a single number, the brightness is not averaged.

[0095] In the above embodiment, it is possible to appropriately change the number and arrangement of the five filters F0 to F4 of the variable ND filter device 804. Furthermore, the rotation direction Cw of the rotating plate 804a is not limited to the counterclockwise direction, and may be the clockwise direction.

[0096] In the above embodiment, the measurement point identification units 205c, 802a turned off each micromirror 30a of the DMD display element 30 during a period when light sources other than the light source to be measured were on, but the light sources other than the light source to be measured may also be turned off.

[0097] In the above embodiment, the DMD duty ratio is changed in three stages between control modes Q1, Q2, and Q3 to Qn, but the present invention is not limited to this, and the DMD duty ratio may be changed in four or more stages between control modes Q1 to Qn, or the DMD duty ratio may be changed in two stages. Also, the DMD duty ratio may be kept constant between control modes Q1 to Qn without being changed.

[0098] In the above embodiment, two specific points are set, the first specific point number n for the high brightness mode and the second specific point number m for the low brightness mode, but three or more specific points may be set. In this case, the specific points may be set to increase as the required brightness decreases.

[0099] In the above embodiment, as shown in FIG. 23, the arrangement of the display period Ton and the non-display period Tof per cycle differs between the control modes Q1 to Qx in the high luminance mode and the control modes Qy to Qn in the low luminance mode, but it may be the same. [Explanation of symbols]

[0100] 1 HUD device 2 Vehicles 3 Windshield 4. Viewer 5 Light source driver 7. Illuminance sensor 10. Lighting Equipment 11 Light source group 11b,11g,11r light source 13 Photosynthetic Division 13a Reflective mirror 13b, 13c Dichroic mirror 15 Prism 15a Slope 15b, 15c Orthogonal plane 18 Projector equipment 18a~18j Sample projector equipment 18k shipment projector equipment 19 Display unit 30 DMD display element 30a Micromirror 40 Projection optical system 43 Light source driver 49 Voltage detection section 50 Transparent Screen 54,55,61 plane mirror 62 Concave mirror 65 Concave mirror drive unit 70 Case 70a opening 71 Translucent part 100 First control unit 200 Second control section 201 Light source control unit 201a Gain setting section 202 Display element control unit 203,807 Storage section 205 Product Data Generation Department 205a Drive capability determination unit 205b Master Data Selection Section 205c Measurement point identification part 205d Output characteristics acquisition section 205e Data correction section 300 Light Source Driver 500 Light Intensity Detector 600 Light source temperature detector 700 Video signal input section 800 Lighting control data generator 801 Sample data acquisition device 802 Master Data Generation Department 802a Measurement point identification part 802b Output characteristics acquisition section 803 Light Meter 803 Meter 804 Variable ND filter device F0~F4 Filter 804a Rotating plate 804b Irradiation range 804c Rotary drive unit 805 Thermostatic chamber glass 806 Room temperature adjustment section 808 Constant temperature bath 809 Inspection light emission unit 810 Shipment data acquisition device 813 Light Meter 814 Variable ND filter device 818 Chamber 819 Inspection light emitter R red light B blue light G green light C illumination light C1 Capacitor G1-G10 grade L display light M Image L1 Inductor M1-M10 Master Data Mc Comparison Data Mx Optimal Master Data P Pulse Q1-Qn, Qa, Qb, Qc, Qd, Qx, Qy control mode V Virtual Image SE video signal SL Required luminance signal SFB light intensity detection signal Ib,Ig,Ir current Df1,Df2 difference value ST Light source temperature signal Bl,Bl1,Bl2,BlA,BlB Luminance range Lb, Lg, Lr Line SV voltage detection signal Dm Lighting control data Tr,Tg,Tb lighting permission period Ax Rotation axis Ay Rotation axis P1~Px,Pm,Pn measurement points Pk Peak value Swa, Swb, Swc, Swg, Swr Switch section Ton display period Tof hidden period J1, J2, J non-use range E1 Overlapping area E2 mode switching value

Claims

1. A plurality of light sources; a light source driver that drives the plurality of light sources; a control unit that turns on the plurality of light sources via the light source driver based on illumination control data; a DMD display element that generates display light based on illumination light emitted by the plurality of light sources; the illumination control data includes first and second control modes for generating the illumination light having a luminance according to a requested luminance; the first and second control modes have different luminance ranges that overlap each other; the control unit switches between the first and second control modes when the required luminance reaches a mode switching value located at a non-edge of an overlapping region where the luminance range of the first control mode and the luminance range of the second control mode overlap. Head-up display device.

2. The mode switching value is set to a median value of the overlapping region. The head-up display device according to claim 1 .

3. The head-up display device includes: a transmission type screen that receives the display light from the DMD display element and displays an image, The DMD display element includes a plurality of micromirrors provided corresponding to pixels of the image; each of the plurality of micromirrors is switched between an ON state in which the illumination light from the light source is reflected toward the transmissive screen and an OFF state in which the illumination light from the light source is reflected in a direction different from the transmissive screen under the control of the control unit; a median value of the luminance range in the first control mode is set to be larger than a median value of the luminance range in the second control mode and a median value of the luminance range in the third control mode; a median value of the luminance range in the second control mode is set to be smaller than a median value of the luminance range in the first control mode and larger than a median value of the luminance range in the third control mode; the control unit adjusts the luminance of the display light by changing a DMD duty ratio, which is a period during which the micromirror is in the on state in one period; the DMD duty ratio of the first control mode is set to be larger than the DMD duty ratio of the second control mode and the DMD duty ratio of the third control mode; the DMD duty ratio in the second control mode is set to be larger than the DMD duty ratio in the third control mode and smaller than the DMD duty ratio in the first control mode; The head-up display device according to claim 1 or 2.

Images