JP6834286B2 - Projector, projection method and program - Google Patents

Description

The present invention is suitable projection apparatus such as a projector using a high-resolution light modulator element, to throw a shadow method, and a program.

In the current situation where products compatible with 4K resolution (resolution of about 4000 pixels in width x 2000 pixels in height) are becoming widespread in TV receivers and displays, projection devices such as data projectors also support high resolution. Various techniques have been proposed. (For example, Patent Document 1)

Japanese Unexamined Patent Publication No. 2012-242626

Including the techniques described in the above patent documents, some light modulation element is irradiated with light from a light source, a light image is formed by the transmitted light or reflected light, and the light is emitted by a lens optical system to be projected. As described above, high resolution is also being studied in a projection device that projects onto a screen surface.

Among these, a DLP (registered trademark) (Digital Light Processing) type projector device in which a micromirror element put into practical use by MEMS (Micro Electro Electro Mechanical Systems) technology, which has become popular in recent years, is used as an optical modulation element will be considered.

For example, when a projector device product compatible with 2K resolution (resolution of about 2000 pixels in width x 1000 pixels in height) is already available, when a projector device using a micromirror element compatible with 4K resolution is newly commercialized, micro If the resolution can be increased without changing the element size of the mirror element, it will be necessary to redesign the hardware other than the micromirror element, such as the light source system and lens optical system around the micromirror element, as the size increases. Since there is no such thing, it can be handled very reasonably.

However, when the resolution is increased without changing the element size, the area of the micromirror per pixel is naturally reduced to about 1/4, for example. In a micromirror element having an array of micromirrors having such a very small area, the micromirrors in the area are fixed in a driving environment in which the same on / off state is maintained in a part of the image for a long time. It is known that there is a tendency for problems to occur.

For example, in a projector device having a trapezoidal correction function of an image, since the image is not displayed in the triangular area at both end of the image, the light from the light source is reflected off to other than the lens optical system. It is necessary to maintain the above, and there is a high possibility that sticking will occur in the micromirror in the area.

In order to prevent the above-mentioned micromirror from sticking, for example, the display content is inverted for a time of more than 100 [microseconds], which corresponds to a period of about 1/100 of the whole for every 1 frame or 2 frames of image projection. It has been confirmed that the refresh operation that turns on / off as much as possible is effective.

However, if the projection operation is continued even during this refresh operation, for example, an operation in which an image other than the original projected image is continuously projected in an area where both ends are cut by the keystone correction function is continuously executed, and the projected image is displayed. The result is a significant deterioration in quality. Therefore, it is necessary to set a black period in which all the light sources are temporarily turned off during the refresh operation.

Hereinafter, the process of setting the black period for refreshing the micromirror element will be described. In the following description, it is assumed that a so-called "single plate type" projection device using one micromirror element and a fluorescent wheel is used.

The main video frequencies recognized by the projector device are the composite video signal established by the National Television Broadcasting System Standardization Committee, the NTSC (National Television System Committee) system, which is the television broadcasting system (standard), and color composite video. There is a PAL (Phase Alternating Line) method which is a signal standard. The vertical synchronization frequency of the NTSC system is 60 Hz (strictly speaking, 59.94 Hz), whereas the vertical synchronization frequency of the PAL system is 50 Hz. Therefore, it is necessary to support the operation of a plurality of input signal frequencies.

FIG. 8A shows the fluorescence wheel rate when the highest frequency in the setting range of the 50 [Hz] system and the frequency of the input signal of 52.1 [Hz] are locked. Since the device is driven at twice the frequency of the input signal inside the device, the numerical value is doubled to 104.2 [Hz]. The lower part of the figure (A) is the R (red), G (green), and B (blue) primary color fields, and the upper part is the sync pulse synchronized with the above field. The same sync pulse is generated and the fluorescent wheel is the same. As shown in the lower part of FIG. (A), by synchronizing with each field and driving the corresponding light emitting elements in synchronization with each other, the primary color light is correctly emitted in time division and the micromirror element is irradiated. In the micromirror element, by displaying an image according to the emitted primary color light, an optical image is formed by the reflected light and projected through the lens optical system.

On the other hand, FIG. 8B shows the fluorescence wheel rate when the frequency of the input signal of 62.0 [Hz], which is the highest frequency in the setting range of the 60 [Hz] system, is locked. Since the device is driven at twice the frequency of the input signal inside the device, the numerical value is doubled to 124.0 [Hz]. Similarly, the lower row of the figure (B) is the primary color fields of R (red), G (green), and B (blue), and the upper row is the sync pulse synchronized with the above fields.

As described above, a lockable "defense range" is set by the device for each fluorescent wheel rate, and here, 94.00 [Hz] to 104.20 [Hz], 60 in the 50 [Hz] system. The case where 102.40 [Hz] to 124.00 [Hz] is set in the [Hz] system is described as an example. As described above, since the frequency of each circuit is driven by twice the frequency of the input signal inside the device, the numerical value of the frequency is doubled. If the input signal has a frequency outside the set range, the device cannot lock the input signal and the projection operation cannot be performed.

The above FIGS. 8 (A) and 8 (B) exemplify the timing when the lock is performed at the highest frequency in the defensive range, respectively.

FIG. 9 shows the fluorescence wheel rate when the input signal of the standard value 50.0 [Hz] of the 50 [Hz] system is locked. The internal synchronization frequency is 100.0 [Hz], and the period of one image frame is exactly 10000 [μsec].

In the above illustration, the ratio of each field period of R, G, and B is set to 1: 1: 1 for the sake of simplicity, but even when other ratios are used, the balance is not lost. , Can deal with frequency-locked signals.

As described above, the period per frame cycle changes according to the frequency of the input signal to be locked. For example, in the case of a 60 [Hz] system, one cycle at 124.0 [Hz] is 8064.5 [μsec], and one cycle at 102.4 [Hz] is 9665.6 [μsec]. The lowest frequency extends the period by about 21% with respect to the highest frequency.

Similarly, in the case of 50 [Hz] system, one cycle in the case of 104.2 [Hz] is 9596.9 [μsec], and one cycle in the case of 94.0 [Hz] is 10638.3 [μsec]. Yes, the lowest frequency extends the period by about 10% relative to the highest frequency.

The processing time for performing the refresh operation also changes depending on the situation in which the input signal is locked. Here, the length of the refresh period
Time length = (fluorescence wheel rate maximum frequency / same minimum frequency) x 100 [μsec]
Defined as
The time length of the refresh period in the 60 [Hz] system is about 121 [μsec].
(≈ (124.0 / 102.4) × 100 [μsec]),
The time length of the refresh period in the 50 [Hz] system is about 111 [μsec].
(≈ (104.2 / 94.0) × 100 [μsec]),
Will be.

In order to execute the above refresh operation, the conventional sequence operation will be described again.
FIG. 10A is a timing chart showing a normal fluorescent wheel rate without executing the refresh operation. The upper row is the sink pulse given to the power supply, and the lower row is the primary color light emitted by the light source driven by the same power supply.

Here, for example, the red light R is obtained from an independent light source by an LED that emits red light, and the green light G is a phosphor applied to the fluorescent wheel shown in FIG. 10 (B) (in the range of "G" in the figure). The fluorescent reflected light obtained by irradiating the coating) with the following blue laser light, and the blue light B is the blue laser light which is an independent light source of the diffuser plate (“B” in the figure) of the fluorescent wheel shown in FIG. 10 (B) above. It shall be obtained as transmitted light of the range).

By issuing the sink pulse shown in the upper part of FIG. 10A toward the power supply, the power supply receiving the pulse performs the following processing.

That is, the power supply that has received the sink pulse of (1) turns off the red LED and turns on the blue laser at the same time. At this time, the blue laser irradiates the G range of the fluorescent wheel, and green light which is the fluorescent reflected light is obtained.

The power supply that has received the sync pulse of (2) adjusts the current value by adjusting the color balance as necessary while keeping the blue laser on. At this time, as shown at timing t11 in the figure, the rotation of the fluorescent wheel in the direction D causes the irradiation range of the blue laser light to become a diffuser of B, so that blue light, which is the transmitted diffused light, can be obtained. For the light source, the synchronization adjustment of the fluorescent wheel is also executed separately at the same time.

The power supply that has received the sync pulse of (3) turns off the blue laser and turns on the red LED at the same time. Red light, which is an independent light source, can be obtained.

In addition to the sequence shown in FIG. 10, consider a case where a black period due to the refresh operation described above is added.

FIG. 11 shows an example of a virtual fluorescence wheel rate in which a black period is arranged at the end of the frame period of the sequence shown in FIG. 10 (A). If this operation can be realized, the refresh operation can be easily executed.

In FIG. 11, the sync pulses of (1) and (2), the period in which the red light R is obtained, and the period in which the green light G is obtained are the same as those in FIG. 10 (A).

Further, where there is a period of blue light B in FIG. 10A, the central angle of the fluorescent wheel is cut by 6 ° in the equivalent of 120 °, and between the sink pulse of (3)'and the sink pulse of (4). It is generating a black period.

When creating a black period while actually maintaining the color balance, it is necessary to move to each sink pulse of (1) and (2) according to the proportion occupied by each color. For example, when the time ratio of each color of R, G, and B is 1: 1: 1, which is equivalent to the central angle of the fluorescent wheel and is (R) 120 °: (G) 120 °: (B) 120 °, it is equivalent to 6 °. If the black period of (R) is created, the sync pulses of (1) to (3) are generated so that (R) 118 °: (G) 118 °: (B) 118 °.

Further, for example, when the time ratio of each color of R, G, and B is 3: 2: 1, and the central angle of the fluorescent wheel is (R) 180 °: (G) 120 °: (B) 60 °, 6 If a black period equivalent to ° is to be created, the sink pulses (1) to (3) are generated so that (R) 177 °: (G) 118 °: (B) 59 ° to maintain the color balance. To do.

The operation performed by the power supply receiving the sink pulses of (1) and (2) is the same as that of FIG. 10 (A), while the sink pulses of (3)'and (4)' are received. The power supply should operate as follows.

That is, the power supply that has received the sink pulse of (3)'turns off the blue laser.
After that, when the sink pulse of (4)'is received, the power supply turns on the red LED.

FIG. 12 (A) is an enlarged view showing the sync pulse portions of the above (3)'and (4)'. Even if the blue laser is turned off by the sync pulse of (3)', the amount of light emitted does not immediately become "0 (zero)" due to the responsiveness of the blue laser, and the red LED due to the sync pulse of (4)'. Even if is turned on, the responsiveness of the red LED does not mean that the amount of light emitted immediately becomes 100%.

In FIG. 12B, it can be seen that the time 160 [μsec] between the sink pulses of (3)'and (4)' is secured. As described above, it takes about 40 [μsec] from when the blue laser is turned off by the sync pulse of (3)'to when the amount of light emitted by the blue laser actually becomes "0 (zero)". It can be seen that a black period of 100 [μsec] can be secured.

When using a product in which the responsiveness of the blue level is poor and it takes more time for the amount of light emitted to reach "0 (zero)" after turning off, the above (3)'and (4)' This is dealt with by further widening the interval between the sync pulses.

The problem here is that the temporal intervals of the sync pulses of (3)'and (4)' above are extremely small. When the sink pulses of (3)'and (4)' are generated and applied to the digital power supply used in this type of product, the time interval is too small, so that the power supply side ( 4) ′ sync pulse cannot be recognized.

In the digital power supply generally used in this type of projection device, the sync pulses need to be separated by at least 500 [μsec]. Therefore, in order to realize the operation as described with reference to FIG. 11, it is necessary to change to a more expensive power supply or newly develop the power supply instead of the digital power supply used in the conventional product.

Therefore, the operation of generating the black period for the refresh operation by using the sync pulse described in FIG. 11 above is extremely unrealistic, and the black is appropriate according to the frequency of the input signal by other means. A way to generate a period is being sought.

The present invention has been made in view of the above circumstances, and an object of the present invention is to respond to the frequency of an input video signal during a projection period without significantly changing the circuits constituting the apparatus. was extremely short time projecting a projection apparatus capable of inserting a black period is not performed to provide a projection shadow method, and a program.

One aspect of the present invention is from at least one of a fluorescence light reflection area having a phosphor that is excited by light from a light emitting element to emit fluorescent light, a transmission area that transmits light from the light emitting element, and the light emitting element. A light image is formed by using a fluorescent wheel provided so that a shielding area that does not emit the light of the above light is arranged side by side in the circumferential direction, a motor that rotationally drives the fluorescent wheel, and light emitted from the fluorescent wheel. While the shielding area is located at the irradiation position of the light from the light emitting element by the rotation of the display element composed of a plurality of micromirrors and the fluorescence wheel, the on / off inversion operation of the micromirrors is performed. It is provided with a control unit that controls the operation.

According to the present invention, it is possible to insert a black period during the projection period, in which projection is not performed for an extremely short time according to the frequency of the input video signal, without significantly changing the circuits constituting the apparatus or the like. It becomes possible.

The block diagram which shows the schematic functional structure of the projector apparatus which concerns on 1st Embodiment of this invention. The plan view explaining the structure of the fluorescent wheel which concerns on this embodiment with reference to the structure of a general fluorescent wheel. The flowchart which shows the processing content at the time of a projection operation which concerns on the same embodiment. The figure which shows the rotation of the fluorescence wheel and the sequence of the projected image with respect to the image signal of the 50 [Hz] system which concerns on the same embodiment. The figure which shows the rotation of the fluorescence wheel and the sequence of the projected image with respect to the 60 [Hz] system image signal which concerns on the same embodiment. The plan view explaining the structure of the fluorescent wheel which concerns on 2nd Embodiment of this invention. The figure which shows the rotation of the fluorescence wheel with respect to each image signal of 50 [Hz] system and 60 [Hz] system which concerns on the same embodiment. A timing chart showing the fluorescence wheel rate when the synchronization of the input signal having the highest frequency in each of the 50 [Hz] system and the 60 [Hz] system is locked. A timing chart showing the fluorescence wheel rate when the synchronization of an input signal of 50 [Hz] is locked. The figure which shows the timing chart which shows the normal fluorescent wheel rate which does not perform a refresh operation, and the configuration example of a fluorescent wheel. A timing chart showing the virtual fluorescence wheel rate when performing a refresh operation. The timing chart which enlarges and shows the sync pulse (3)', (4)' part of FIG.

(First Embodiment)
Hereinafter, a first embodiment when the present invention is applied to a DLP (registered trademark) type projector device will be described with reference to the drawings.

FIG. 1 is a diagram showing a schematic functional configuration of the projector device 10 according to the present embodiment. In the figure, the input unit 11 is, for example, a pin jack (RCA) type video input terminal, a D-sub15 type RGB input terminal, an HDMI (registered trademark) (High-Definition Multimedia Interface) terminal, and a USB (Universal Serial Bus) terminal. It is composed of. The analog or digital image signals of various standards input to the input unit 11 are digitized as needed by the input unit 11 and then sent to the image conversion unit 12 via the system bus SB.

The image conversion unit 12, also generally referred to as a scaler or formatter, unifies the input digital value image data into image data in a predetermined format suitable for projection and sends it to the projection processing unit 13.

The projection processing unit 13 has a frame rate according to the transmitted image data, for example, if the frequency of the original image signal is 50 [Hz], it is around 100 [frames / second] (if it is 60 [Hz]). The micromirror element 14, which is a spatial light modulation element, is driven to be displayed by a faster time division drive obtained by multiplying (around 120 [frames / second]) by the number of divisions of color components and the number of display gradations. ..

The micromirror element 14 displays an image by individually turning on / off each tilt angle of high resolution, for example, 4000 pixels wide × 2000 pixels long, arranged in an array at high speed. An optical image is formed by the reflected light.

On the other hand, the primary color lights of R, G, and B are cyclically emitted from the light source unit 15 in a time division manner. The primary color light from the light source unit 15 is totally reflected by the mirror 16 and irradiated to the micromirror element 14.

Then, an optical image is formed by the reflected light of the micromirror element 14, and the formed optical image is projected and displayed on a screen (not shown) to be projected via the projection lens unit 17.

The light source unit 15 has an LED (light emitting diode) that emits red light, an LD (semiconductor laser) that emits blue laser light, and a fluorescence wheel that excites green light by irradiating a phosphor with the blue laser light. To do.

The projection processing unit 13 will describe the formation of an optical image by displaying an image on the micromirror element 14, the light emission of each of the LEDs and LDs as a light emitting element in the light source unit 15, and the rotation of the fluorescence wheel. While executing under the control of the CPU 19, it sends a sink pulse for field switching to the digital power supply 18, and also sends and receives various command signals for power supply control to and from the digital power supply 18.

The digital power supply 18 generates and supplies a large number of DC voltage values required for each circuit from the AC power supply (not shown) provided for the projector device 10, and also supplies the light source unit 15 with LEDs and LDs. It supplies the power required to drive the light source and rotate the fluorescent wheel.

The CPU 19 controls all the operations of the above circuits. The CPU 19 is directly connected to the main memory 20 and the program memory 21. The main memory 20 is composed of, for example, SRAM, and functions as a work memory of the CPU 19. The program memory 21 is composed of an electrically rewritable non-volatile memory, and stores an operation program executed by the CPU 19 and various standard data. In other words, the CPU 19 uses the main memory 20 and the program memory 21 to execute the control operation in the projector device 10.

The CPU 19 executes various projection operations in response to a key operation signal from the operation unit 22.
The operation unit 22 includes a key operation unit provided on the main body of the projector device 10 and an infrared light receiving unit that receives infrared light from a remote controller (not shown) dedicated to the projector device 10, and the user can operate the keys on the main body. The key operation signal based on the key operated by the unit or the remote controller is directly output to the CPU 19.

The CPU 19 is also connected to the voice processing unit 23 via the system bus SB. The audio processing unit 23 includes a sound source circuit such as a PCM sound source, converts audio data given via the system bus SB during projection operation into analog, drives the speaker unit 24 to emit loud sound, or if necessary, a beep sound or the like. To generate.

FIG. 2A is a plan view showing the configuration of the fluorescent wheel 31 provided in the light source unit 15. In the figure (A), in the vicinity of the outer peripheral edge of the fluorescent wheel 31, the transmission area 31T for transmitting the blue laser light while diffusing it and the green phosphor are coated in a circumferential shape to obtain the blue laser light. The green light reflection area 31G, which is excited by irradiation and emits green light as fluorescent light and is generated as reflected light, is arranged side by side in the circumferential direction to form a disk surface. The fluorescent wheel 31 is rotationally driven by a motor (not shown).

Here, for the sake of simplicity, the central angle of the transmission area 31T with respect to the fluorescent wheel 31 is 120 °, which is equivalent to 1/3, and the central angle of the green light reflection area 31G with respect to the fluorescent wheel 31 is 240 °, which is equivalent to 2/3. Suppose there is.

Further, even if the blue laser light is irradiated without intentionally applying the phosphor to both ends of the portion of the green light reflection area 31G coated with the phosphor and the portion adjacent to the transmission area 31T, the light is transmitted. And shield areas 31B1 and 31B2 that do not reflect either are provided.

Here, the two shielding areas 31B1 and 31B2 are set with different widths in the circumferential direction so that the central angles with respect to the fluorescent wheel 31 are different as shown in the figure.

That is, when the maximum rotation speed in the 60 [Hz] system is set to, for example, 124 [rpm], the shielding area 31B1 requires a black period of 100 in the time required for one revolution, about 8065 [μsec]. In order to secure [μsec], the central angle with respect to the fluorescent wheel 31 is formed to be about 4.46 °.

On the other hand, the shielding area 31B2 requires black in the time required for one lap, about 9597 [μsec], when the maximum rotation speed is set to, for example, 104.2 [rpm] in the 50 [Hz] system. In order to secure a period of 100 [μsec], the central angle with respect to the fluorescent wheel 31 is formed to be about 3.75 °.

FIG. 2B is a plan view showing a configuration example of a conventional fluorescent wheel PR for a general hybrid light source for reference. The transmission area PRT and the green light reflection area PRG are combined to form a disk shape. The transmission area PRT is made of hard and highly heat-resistant glass, and the green light reflection area PRG is made of metal. It is bonded to form a disk-shaped fluorescent wheel PR. Therefore, it is allowed that there are areas PRB1 and PRB2 where the phosphor cannot be applied due to the influence of the adhesive. The central angles of these areas PRB1 and PRB2 with respect to the fluorescent wheel PR are defined to be within, for example, about 0.5 ° to 2 °.

As shown in FIG. 2 (A), in the present embodiment, the shielding areas 31B1 and 31B2, which are wide and set with different central angles, are not intentionally coated with the phosphor, so that the projection operation is in progress as described later. It produces a black period in.

Next, the operation of the above embodiment will be described.
The operation shown below basically indicates a process executed by the projection processing unit 13 under the control of the CPU 19.

FIG. 3 is a flowchart showing a projection operation from the time when the power is turned on, which is mainly executed by the projection processing unit 13. At the initial stage of turning on the power, the projection processing unit 13 sets 60 [Hz] as the default video signal frequency, and reads a prepared splash screen image or a preset wallpaper image from the program memory 21 (step S101). ), The initial image is displayed by displaying the micromirror element 14, and the light source unit 15 sequentially drives the red light R, the green light G, and the blue light B to emit light in a time-divided manner to execute the projection operation. (Step S102).

While executing this projection operation, the projection processing unit 13 further determines whether a new image signal is input via the input unit 11 or whether the image signal input to the input unit 11 is switched (step S103). ..

If it is determined that neither new image signal input nor image signal switching has occurred (No in step S103), the projection processing unit 13 returns to the processing from step S102 and continues the projection operation.

In this way, the processes of steps S102 and S03 are repeatedly executed, and while the same projection operation is continued, the input of a new image signal and the switching of the image signal are waited for.

When it is determined in step S103 that a new image signal is input or that switching of the image signal has occurred (Yes in step S103), the projection processing unit 13 receives the image signal newly input there. After synchronously locking, it is determined whether or not it is necessary to switch the frequency between the 50 [Hz] system and the 60 [Hz] system (step S104).

If it is determined that the frequency system does not need to be switched and the newly input image signal has the same frequency system (No in step S104), the frequencies of 50 [Hz] and 60 [Hz] are used. The switching between the systems is set to be invalid (step S105), and the process returns to the process from step S102 again.

However, even if the frequency is not switched between the 50 [Hz] system and the 60 [Hz] system, the frequency of the image signal actually input is, for example, the lockable defensive range of the 60 [Hz] system is 102.40. It is set as [Hz] to 124.00 [Hz], and if the frequency is different between the image signal that was input so far and the image signal that is newly input this time within the defensive range, it is projected. As described above, the processing unit 13 locks the newly input image signal and continues the projection operation according to the frequency.

FIG. 5 shows the drive of the fluorescence wheel 31 (FIG. 5 (A)) and the sequence of the projected image when an image signal of 60.0 [Hz] is input in the 60 [Hz] system, as in the initial setting. It is a figure which shows (FIG. 5 (B)). Assuming that the fluorescent wheel 31 is irradiated with the blue laser light from the upper side to the lower side of the paper in the drawing, the fluorescent wheel 31 is rotationally driven in the counterclockwise direction D2 as shown in the drawing.

In FIG. 3A, in addition to the configuration of the fluorescent wheel 31, the light emitting period (R) by the red LED, which is a single light source, is superimposed as shown by the broken line. The light emission period by the red LED is a period in which the irradiation position of the blue laser light is located at the first central angle of 120 ° of the green light reflection area 31G including the shielding area 31B2, and the projection operation in the R field is performed. During the period of execution, the blue laser has stopped emitting light.

After that, the red LED is stopped and the blue laser is started at the same time, and the fluorescent wheel 31 is used for a period corresponding to the central angle of 115.54 ° (= 120 ° -4.46 °) of the green light reflection area 31G. The projected light in the G field is executed by the reflected light of.

After that, the blue laser continues to emit light, but while the shielding area 31B1 is located at the laser light irradiation position due to the rotation of the fluorescent wheel 31, the green light is not excited due to the absence of the phosphor, and the micromirror element 14 There is a black period in which the light from the light source unit 15 is not irradiated.

After that, when the fluorescence wheel 31 is further rotated and the blue laser light is irradiated to the transmission area 31T, the projection operation in the B field by the blue light transmitted and diffused in the transmission area 31T is executed.

As described above, one frame of image projection is executed in the order of R field, G field, black period, and B field, and one frame when an image signal of 60.0 [Hz] is input. The period of minutes is 8333.3 [μsec] as shown in the figure.

At this time, the black period due to the shielding area 31B1 is about 103 [μsec], and the minimum time 100 [μsec] that allows the refresh operation of a part of the micromirror element 14 that is off by keystone correction or the like is possible. Is secured.

Further, in step S104, when it is determined that the frequency needs to be switched between the 50 [Hz] system and the 60 [Hz] system (Yes in step S104), the projection processing unit 13 temporarily sets the light source unit 15. After stopping the light emission of both the red LED and the blue laser (step S106), the rotation direction of the fluorescent wheel 31 is set to be reversed (step S107).

After that, the projection processing unit 13 searches for the rotation speed of the fluorescence wheel 31 (step S108), and determines whether or not the rotation speed is correct based on whether or not the frequency is twice the frequency of the input image signal (step). S109).

If it is determined that the rotation speed is not yet correct (No in step S109), the projection processing unit 13 returns to the process from step S108, and thereafter searches for the rotation speed of the fluorescent wheel 31 to obtain the correct rotation speed. Wait until it rises to.

Then, in step S109, when it is determined that the rotation speed of the fluorescent wheel 31 has increased to the correct rotation speed (Yes in step S109), the projection processing unit 13 again synchronizes with the rotation of the fluorescent wheel 31 and the red LED. After starting the light emission of the blue laser together (step S110), the process returns to the process from step S102.

In this way, the projection operation based on the newly input image signal is executed.

FIG. 4 shows the driving of the fluorescence wheel 31 (FIG. 4 (A)) and the sequence of the projected image (FIG. 4 (B)) when an image signal of 50.0 [Hz] is input in the 50 [Hz] system. ). Assuming that the fluorescent wheel 31 is irradiated with the blue laser light from the upper side to the lower side of the paper in the drawing, the fluorescent wheel 31 is rotationally driven in the clockwise direction D1 as shown in the drawing.

In FIG. 3A, in addition to the configuration of the fluorescent wheel 31, the light emitting period (R) by the red LED, which is a single light source, is superimposed as shown by the broken line. The light emission period by the red LED is a period in which the irradiation position of the blue laser light is located at the first central angle of 120 ° of the green light reflection area 31G including the shielding area 31B1, and the projection operation in the R field is performed. During the period of execution, the blue laser has stopped emitting light.

After that, the red LED is stopped and the blue laser is started at the same time, and the fluorescent wheel 31 is used for a period corresponding to the central angle of 116.25 ° (= 120 ° -3.75 °) of the green light reflection area 31G. The projected light in the G field is executed by the reflected light of.

After that, the blue laser continues to emit light, but while the shielding area 31B2 is located at the laser light irradiation position due to the rotation of the fluorescent wheel 31, the green light is not excited due to the absence of the phosphor, and the micromirror element 14 There is a black period in which the light from the light source unit 15 is not irradiated.

After that, when the fluorescence wheel 31 is further rotated and the blue laser light is irradiated to the transmission area 31T, the projection operation in the B field by the blue light transmitted and diffused in the transmission area 31T is executed.

As described above, one frame of image projection is executed in the order of R field, G field, black period, and B field, and one frame when an image signal of 50.0 [Hz] is input. The minute cycle is 10000 [μsec] as shown.

At this time, the black period due to the shielding area 31B2 is about 104 [μsec], and the minimum time 100 [μsec] that allows the refresh operation of a part of the micromirror element 14 that is off by keystone correction or the like is possible. Is secured.

In this way, by inverting the rotation direction of the fluorescence wheel 31 between the 50 [Hz] system image signal and the 60 [Hz] system image signal, one image frame is always in the R field, G field, black period, and The projection operation can be executed by configuring in the order of the B fields, and the control sequence between the fields by the projection processing unit 13 can be simplified.

In the above embodiment, for the sake of simplicity, it is assumed that the ratio of the periods of the R field, the G field, and the B field constituting one image frame is 1: 1: 1, and the period corresponding to the G field. The case where the black period is arranged inside is taken as an example to explain.

However, in the actual product, the periods of the R field, the G field, and the B field are set in consideration of the color balance and the length of the black period, and even in the configuration of the fluorescent wheel 31, these periods are set. The central angles of the transmission area 31T and the green light reflection area 31G with respect to the fluorescence wheel 31 are set according to the ratio.

(Second Embodiment)
Hereinafter, a second embodiment when the present invention is applied to a DLP (registered trademark) type projector device will be described with reference to the drawings.

The schematic functional configuration of the projector device 10'according to the present embodiment is the same as that shown in FIG. 1, and the same reference numerals are used for the same parts, and the illustration and description thereof will be omitted.

The light source unit 15 in the projector device 10'is a red LED (light emitting diode) that emits blue light, an LD (semiconductor laser) that emits blue laser light for excitation, and a phosphor that is irradiated with the blue laser light. It shall have a fluorescent wheel that excites light and green light.

FIG. 6 is a plan view showing the configuration of the fluorescent wheel 41 provided in the light source unit 15. In the figure, the fluorescent wheel 41 is coated with a red phosphor (second fluorescent substance) in a circumferential shape and excited by irradiation with the blue laser beam to use red light (second fluorescent light) as reflected light. The generated red light reflection area (second fluorescence light reflection area) 41R and the green phosphor (first fluorescence body) are coated in a circumferential shape and excited by irradiation with the blue laser light to produce green light (green light (first fluorescence)). A disk surface is composed of a green light reflection area (first fluorescence light reflection area) 41G that generates (first fluorescence light) as reflected light.

Here, for the sake of simplicity, the red light reflection area 41R and the green light reflection area 41G are configured by equally dividing the fluorescent wheel 41 into two parts.

Further, even if the portion straddling the boundary between the red light reflection area 41R and the green light reflection area 41G is not intentionally coated with a phosphor and is irradiated with blue laser light, both transmission and reflection are performed. Shielding areas 41B1 and 41B2 are provided.

Here, the two shielding areas 41B1 and 41B2 are set with different widths in the circumferential direction so that the central angles with respect to the fluorescent wheel 31 are different as shown in the figure.

That is, when the maximum rotation speed in the 50 [Hz] system is set to, for example, 104.2 [rpm], the shielding area 41B1 requires black in the time required for one lap, about 9597 [μsec]. In order to secure a period of 100 [μsec], the central angle with respect to the fluorescent wheel 41 is formed to be about 3.75 °.

On the other hand, the shielding area 41B2 requires a black period of 100 in the time required for one lap, about 8065 [μsec], when the maximum rotation speed is set to, for example, 124 [rpm] in the 60 [Hz] system. In order to secure [μsec], the central angle with respect to the fluorescent wheel 31 is formed to be about 4.46 °.

By presenting these wide shielding areas 41B1 and 41B2 that are not intentionally coated with the phosphor and are set with different central angles, a black period during the projection operation is generated as described later.

Next, the operation of the above embodiment will be described.
FIG. 7A is a diagram showing the driving of the fluorescence wheel 41 when a 50 [Hz] system image signal is input. Assuming that the fluorescent wheel 41 is irradiated with the blue laser light from the upper side to the lower side of the paper in the drawing, the fluorescent wheel 41 is rotationally driven in the clockwise direction D1 as shown in the drawing.

In FIG. 6A, in addition to the configuration of the fluorescent wheel 41, the light emitting period (B) by the blue LED, which is a single light source, is superimposed as shown by a broken line. The light emitting period by the blue LED is a period of 120 ° at a central angle centered on the shielding area 41B2, and the blue laser stops emitting light during the period when the projection operation in the B field is executed. There is.

After that, the emission of the blue LED and the start of the emission of the blue laser are executed at the same time, and the fluorescent wheel is used for a period equivalent to the central angle of 118.13 ° (= 120 ° -3.75 ° / 2) of the red light reflection area 41R. The projection operation in the R field is executed by the reflected light from 41.

After that, the blue laser continues to emit light, but while the shielding area 41B1 is located at the laser light irradiation position due to the rotation of the fluorescent wheel 41, the red light and green light are not excited due to the absence of the phosphor, and the micro The mirror element 14 has a black period in which the light from the light source unit 15 is not irradiated.

After that, when the fluorescence wheel 41 is further rotated and the blue laser light is applied to the green light reflection area 41G, the projection operation in the G field by the green light excited in the green light reflection area 41G is executed.

As described above, the image projection for one frame is executed in the order of the R field, the black period, the G field, and the B field. For example, 1 when an image signal of 50.0 [Hz] is input. The period for each frame is 10000 [μsec].

At this time, the black period due to the shielding area 31B1 is about 104 [μsec], and the minimum time 100 [μsec] that allows the refresh operation of a part of the micromirror element 14 that is off by keystone correction or the like is possible. Can be secured.

FIG. 7B is a diagram showing the driving of the fluorescence wheel 41 when a 60 [Hz] system image signal is input. Even when the fluorescent wheel 41 is irradiated with the blue laser light from the upper side to the lower side of the paper in the drawing, the fluorescent wheel 41 is rotationally driven in the clockwise direction D1 as shown in the drawing.

In FIG. 3B, in addition to the configuration of the fluorescent wheel 41, the light emitting period (B) by the blue LED, which is a single light source, is superimposed as shown by a broken line. The light emitting period by the blue LED is a period of 120 ° at a central angle centered on the shielding area 41B1, and the blue laser stops emitting light during the period when the projection operation in the B field is executed. There is.

After that, the emission of the blue LED and the start of the emission of the blue LED are executed at the same time, and the fluorescent wheel is used for a period corresponding to the central angle of 117.77 ° (= 120 ° -4.46 ° / 2) of the green light reflection area 41G. The projected light in the G field is executed by the reflected light from 41.

After that, the blue laser continues to emit light, but while the shielding area 41B2 is located at the laser light irradiation position due to the rotation of the fluorescent wheel 41, the green light and red light are not excited due to the absence of the phosphor, and the micro The mirror element 14 has a black period in which the light from the light source unit 15 is not irradiated.

After that, when the fluorescent wheel 41 is further rotated and the blue laser light is applied to the red light reflection area 41R, the projection operation in the R field by the red light excited in the red light reflection area 41R is executed.

As described above, the image projection for one frame is executed collectively in the order of the R field, the B field, the G field, and the black period. For example, 1 when an image signal of 60.0 [Hz] is input. The period for each frame is 8333.3 [μsec].

At this time, the black period due to the shielding area 41B2 is about 103 [μsec], and the minimum time 100 [μsec] that allows the refresh operation of a part of the micromirror element 14 that is off by keystone correction or the like is possible. Can be secured.

In this way, by making the rotation direction of the fluorescence wheel 41 the same direction for the 50 [Hz] system image signal and the 60 [Hz] system image signal, it is necessary to reverse the rotation direction of the fluorescence wheel 41 at the time of signal switching. The projection operation synchronized with the new image signal can be started immediately.

As described in detail above, according to the present embodiment, a black period in which projection is not performed for an extremely short time according to the frequency of the input video signal during the projection period without significantly changing the circuits constituting the apparatus or the like. Can be inserted.

Further, in the above embodiment, a plurality of shielding areas having different central angles are provided on the fluorescent wheel, and the light emission timing of the light emitting element is controlled so that the light from the light emitting element is selectively irradiated to one of the plurality of shielding areas. Therefore, it is possible to set a black period having an appropriate time length corresponding to the frequency of the input image signal.

Further, in the first embodiment, since one is selected from a plurality of shielding areas and the rotation direction of the fluorescent wheel is variably set as appropriate, each color field and black constituting one image frame are set. It is possible to deal with the switching of image signals without changing the order of the periods.

Further, in the above embodiment, by arranging the shielding area on the fluorescent wheel so as to be a boundary between a plurality of colored light areas, the area where the phosphor cannot be applied is effectively utilized, and the timing control of the black period is performed. It can be simplified.

In the first embodiment, the light source unit obtains the red LED as an independent light source and the light from the blue laser via the fluorescent wheel 31, and the light source unit in the second embodiment. Has described a case where a blue LED as an independent light source and a case where light from a blue laser is obtained through a fluorescent wheel 41 to obtain red light and green light, respectively, but the present invention is limited to such a light emitting element and a color combination. It's not a thing.

In addition, the present invention is not limited to the above-described embodiment, and can be variously modified at the implementation stage without departing from the gist thereof. In addition, the functions executed in the above-described embodiment may be combined as appropriate as possible. The above-described embodiments include various steps, and various inventions can be extracted by an appropriate combination according to a plurality of disclosed constitutional requirements. For example, even if some constituent requirements are deleted from all the constituent requirements shown in the embodiment, if the effect is obtained, the configuration in which the constituent requirements are deleted can be extracted as an invention.

Hereinafter, the inventions described in the claims of the original application of the present application will be added.
[Claim 1]
At least one of a fluorescence light reflection area having a phosphor that is excited by light from a light emitting element and emitting fluorescent light, a transmission area that transmits light from the light emitting element, and a shielding area that does not emit light from the light emitting element. Fluorescent wheels that are installed side by side in the circumferential direction
The motor that rotates and drives the fluorescent wheel and
A display element composed of a plurality of micromirrors that forms an optical image using the light emitted from the fluorescent wheel, and
A control unit that controls the on / off reversal operation of the micromirror while the shielding area is located at the light irradiation position from the light emitting element by the rotation of the fluorescent wheel.
Projection device equipped with.
[Claim 2]
It is provided with a projection unit that projects the light image formed by the display element toward the object to be projected.
The control unit controls the rotation of the fluorescent wheel so that the light emitting element continues to emit light while the shielding area is located at the irradiation position of the light from the light emitting element.
The projection device according to claim 1.
[Claim 3]
The light emitting element includes a semiconductor laser that emits laser light.
The fluorescent light reflecting area includes a first fluorescent light reflecting area in which a first phosphor is applied in a circumferential shape, excited by irradiation with the laser light to emit the first fluorescent light, and generated as reflected light. A second phosphor having a wavelength band different from that of the first phosphor is coated in a circumferential shape, excited by irradiation with the laser beam to emit the second fluorescent light, and generated as reflected light. Includes fluorescent light reflection area and
The projection device according to claim 1 or 2.
[Claim 4]
The projection according to claim 3, wherein the shielding area is provided at the boundary between the fluorescence light reflection area and the transmission area, or the boundary between the first fluorescence light reflection area and the second fluorescence light reflection area. apparatus.
[Claim 5]
The projection device according to any one of claims 1 to 4, wherein the shielding area is provided on the fluorescence light reflection area side.
[Claim 6]
The fluorescent wheel is provided with a plurality of shielding areas having different central angles.
Further provided is a control unit that controls the light emission timing of the light emitting element so that the light from the light emitting element is selectively irradiated to one of the plurality of shielding areas.
The projection device according to any one of claims 1 to 5.
[Claim 7]
The projection device according to claim 2, wherein the control unit variably sets the rotation direction of the fluorescent wheel in response to the selection of the shielding area.
[Claim 8]
At least one of a fluorescence light reflection area having a phosphor that is excited by light from a light emitting element and emitting fluorescent light, a transmission area that transmits light from the light emitting element, and a shielding area that does not emit light from the light emitting element. Fluorescent wheels that are installed side by side in the circumferential direction
The motor that rotates and drives the fluorescent wheel and
A light source device equipped with.
[Claim 9]
At least one of a fluorescence light reflection area having a phosphor that is excited by light from a light emitting element and emitting fluorescent light, a transmission area that transmits light from the light emitting element, and a shielding area that does not emit light from the light emitting element. From a plurality of micromirrors that form an optical image using a fluorescent wheel provided so as to be arranged side by side in the circumferential direction, a motor that rotationally drives the fluorescent wheel, and light emitted from the fluorescent wheel. It is a projection method with a device including a configured display element.
A projection method including a control step for controlling the on / off reversal operation of the micromirror while the shielding area is located at the irradiation position of light from the light emitting element by the rotation of the fluorescence wheel.
[Claim 10]
At least one of a fluorescence light reflection area having a phosphor that is excited by light from a light emitting element and emitting fluorescent light, a transmission area that transmits light from the light emitting element, and a shielding area that does not emit light from the light emitting element. From a plurality of micromirrors that form an optical image using a fluorescent wheel provided so as to be arranged side by side in the circumferential direction, a motor that rotationally drives the fluorescent wheel, and light emitted from the fluorescent wheel. A program executed by a computer having a built-in display element and a device including the above-mentioned computer.
A program that functions as a control unit that controls the on / off reversal operation of the micromirror while the shielding area is located at the irradiation position of light from the light emitting element by the rotation of the fluorescent wheel.

10, 10'... Projector device,
11 ... Input section,
12 ... Image conversion unit,
13 ... Projection processing unit,
14 ... Micromirror element (display element),
15 ... Light source,
16 ... Mirror,
17 ... Projection lens section,
18 ... Digital power supply,
19 ... CPU,
20 ... Main memory,
21 ... Program memory,
22 ... Operation unit,
23 ... Voice processing unit,
24 ... Speaker section,
31 ... Fluorescent wheel,
31B1, 31B2 ... Shielding area,
31G ... Green light reflection area (fluorescence light reflection area),
31T ... Transparent area,
41 ... Fluorescent wheel,
41B1, 41B2 ... Shielding area,
41G ... Green light reflection area (first fluorescence light reflection area),
41R ... Red light reflection area (second fluorescent light reflection area),
SB ... System bus.

Claims (9)

At least one of a fluorescence light reflection area having a phosphor that is excited by light from a light emitting element and emitting fluorescent light, a transmission area that transmits light from the light emitting element, and a shielding area that does not emit light from the light emitting element. Fluorescent wheels that are installed side by side in the circumferential direction
The motor that rotates and drives the fluorescent wheel and
A display element composed of a plurality of micromirrors that forms an optical image using the light emitted from the fluorescent wheel, and
A control unit that controls the on / off reversal operation of the micromirror while the shielding area is located at the light irradiation position from the light emitting element by the rotation of the fluorescent wheel.
Projection device equipped with. It is provided with a projection unit that projects the light image formed by the display element toward the object to be projected.
The projection device according to claim 1, wherein the control unit controls the rotation of the fluorescent wheel so that the light emitting element continues to emit light while the shielding area is located at the irradiation position of the light from the light emitting element. .. The light emitting element includes a semiconductor laser that emits laser light.
The fluorescent light reflecting area includes a first fluorescent light reflecting area in which a first phosphor is applied in a circumferential shape, excited by irradiation with the laser light to emit the first fluorescent light, and generated as reflected light. A second phosphor having a wavelength band different from that of the first phosphor is coated in a circumferential shape, excited by irradiation with the laser beam to emit the second fluorescent light, and generated as reflected light. Fluorescent light reflection area and
The projection apparatus according to claim 1 or 2. The projection according to claim 3, wherein the shielding area is provided at the boundary between the fluorescence light reflection area and the transmission area, or the boundary between the first fluorescence light reflection area and the second fluorescence light reflection area. apparatus. The projection device according to any one of claims 1 to 4, wherein the shielding area is provided on the fluorescence light reflection area side. The fluorescent wheel is provided with a plurality of shielding areas having different central angles.
The projection device according to any one of claims 1 to 5, further comprising a control unit that controls the light emission timing of the light emitting element so that the light from the light emitting element is selectively irradiated to one of the plurality of shielding areas. The projection device according to claim 6 , wherein the control unit variably sets the rotation direction of the fluorescent wheel in response to the selection of the shielding area. At least one of a fluorescence light reflection area having a phosphor that is excited by light from a light emitting element and emitting fluorescent light, a transmission area that transmits light from the light emitting element, and a shielding area that does not emit light from the light emitting element. From a plurality of micromirrors that form an optical image using a fluorescent wheel provided so as to be arranged side by side in the circumferential direction, a motor that rotationally drives the fluorescent wheel, and light emitted from the fluorescent wheel. It is a projection method with a device including a configured display element.
A projection method including a control step for controlling the on / off reversal operation of the micromirror while the shielding area is located at the irradiation position of light from the light emitting element by the rotation of the fluorescence wheel. At least one of a fluorescence light reflection area having a phosphor that is excited by light from a light emitting element and emitting fluorescent light, a transmission area that transmits light from the light emitting element, and a shielding area that does not emit light from the light emitting element. From a plurality of micromirrors that form an optical image using a fluorescent wheel provided so as to be arranged side by side in the circumferential direction, a motor that rotationally drives the fluorescent wheel, and light emitted from the fluorescent wheel. A program executed by a computer having a built-in display element and a device including the above-mentioned computer.
A program that functions as a control unit that controls the on / off reversal operation of the micromirror while the shielding area is located at the irradiation position of light from the light emitting element by the rotation of the fluorescent wheel.