JP2009251459A - Projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a projector which has improved reliability by suppressing the output of projection devices, and displays a clear image on a screen. <P>SOLUTION: The projector includes: a projector control means which generates a projection signal on the basis of a predetermined input signal; and the plurality of projection devices which display an image by scanning the screen with light beams on the basis of the projection signal. In the projector, the projector control means has a synchronization control part which branches the projection signal and outputs the branched signals to the respective projection devices, each of the projection devices includes: a light source unit which emits a light beam; a scanning means which scans the light beam emitted from the light source unit; and a projection device control means which controls the scanning means in a scannable region 40 on the screen, the respective projection devices are arranged side by side in such a way that the central optical axes of the respective projection devices are parallel to each other, and light beams are scanned synchronized with each other at the superimposed part of the scannable region 40 of the respective projection devices, whereby the image is displayed on the screen. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a projector that forms an image by scanning a screen with a light beam such as a laser beam.

Conventionally, there has been proposed a laser projector that displays an image by scanning a screen with a light beam such as a laser beam. Many proposals have been made to clarify the image displayed on the screen by the laser projector. For example, Japanese Patent Laid-Open No. 6-109992 (Patent Document 1) proposes a large image display device that can project a large screen image with high brightness on a screen using a plurality of laser projectors. Yes.
JP-A-6-109992

  In the proposal of Patent Document 1, laser projectors are arranged at different angles so that the central optical axes of the laser projectors intersect on a screen installed at a position separated by a predetermined distance. For this reason, compared with the projection screen of the laser projector arranged in front of the screen, the vicinity of both ends of the projection screen of the laser projector arranged in the periphery is a distorted screen. Therefore, there is a possibility that the image quality may be deteriorated when the projected images are overlapped, and the distance from the screen for clearly displaying the image is limited. Furthermore, since the laser beams to be scanned overlap each other, there is a problem in that the energy of the overlapping laser beams becomes higher than a predetermined value.

  In order to solve the above-described problem, the present invention arranges a plurality of projection devices side by side so that the central optical axes of the projection devices are parallel to each other, and forms an image at an overlapping portion of the scannable region of each projection device. By doing so, the projector can easily display a clear image on the screen.

  The projector according to the present invention includes a projector control unit that generates a projection signal based on a predetermined input signal, and a plurality of projection devices that display an image by scanning a screen with a light beam based on the projection signal. The projector control means includes a synchronization control unit that divides the projection signal and sends the projection signal to each projection device, and each projection device includes a light source device that emits a light beam and a light beam emitted from the light source device. Scanning means, and projection device control means for controlling the scanning means within a scannable region on the screen, and the projection devices are arranged such that the central optical axes of the projection devices are parallel to each other. Are arranged in parallel, and an image is displayed on the screen by scanning the light beam synchronously at the overlapping portion of the scannable region of each projection device.

  The synchronization control unit is configured to output the projection signals at predetermined different time intervals so that a position of a projection point formed by scanning a laser beam that is one of the light beams from each projection device is shifted. This is sent to the projection device.

  The projector according to the present invention further includes a distance measuring device, and the projector control means includes a distance calculation unit that calculates a distance from the screen, and determines an overlapping portion of the scannable region based on the distance from the screen. Is.

  According to the present invention, a plurality of projection devices are provided, and the projection devices are arranged side by side so that the central optical axes of the projection devices are parallel to each other, and are synchronized in the overlapping portion of the scanable areas of the projection devices. By scanning the light beam, it is possible to provide a projector that can suppress the output of each projection device and increase the reliability, and can easily display a clear image on the screen.

  The laser projector 10 of the best mode for carrying out the present invention includes a projector control means 20 that generates a projection signal based on a predetermined input signal, and a laser beam that is one of light beams based on the projection signal. A plurality of projection devices 1 that display an image by scanning above, the projector control means 20 includes a synchronization control unit 31 that branches the projection signal and sends it to each projection device 1, Each projection device 1 includes a laser light emitter 8 that is a light source device that emits a laser beam, a scanning unit that scans the laser beam emitted from the laser light emitter 8, and a scanable area 40 on the screen 9. Projection device control means 2 for controlling the scanning means, and the projection devices 1 are arranged in parallel so that the central optical axes X of the projection devices 1 are parallel to each other. In the overlapping portion of the scanning region 40 of the shadow device 1, by scanning the laser beam in synchronization, and displays the image on a screen.

  Then, the synchronization control unit 31 sends the projection signal to each projection apparatus 1 at predetermined different time intervals so that the position of the projection point 42 formed by scanning the laser beam from each projection apparatus 1 is shifted. To be sent.

  Further, the laser projector 10 of the present invention includes a distance measuring device 50, and the projector control means 20 has a distance calculation unit 33 for calculating the distance to the screen 9, and can be scanned based on the distance to the screen 9. The overlapping part of the area 40 is determined.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. As shown in FIG. 1, a laser projector 10 according to one embodiment of the present invention has a substantially rectangular parallelepiped shape and incorporates three projectors 1. The projection apparatus 1 includes a laser light emitter that is a light source device that emits a laser beam, a reflection means as a scanning means that scans the laser beam emitted from the laser light emitter, a motor, and the like. It is arranged in parallel in the left-right direction so that the central optical axes X of each projection device 1 are parallel to each other, and the projection port 14 of the projection device 1 is disposed on the front plate 12 that is the side plate in front of the main body case, An optical distance measuring device 50 is disposed in the vicinity of the projection port 14. The distance measuring device 50 is not limited to the optical type, and various types such as an ultrasonic type can be adopted.

  The top plate 11 as a main body case has a key / indicator section 29. The key / indicator section 29 has keys and indicators such as a power switch key and a power indicator for notifying whether the power is on or off. It is equipped with.

  Further, on the back of the main body case, an input / output connector portion provided with a USB terminal, a D-SUB terminal for inputting image signals, an S terminal, an RCA terminal, etc. on the back plate, various terminals 13 such as a power adapter plug, a memory (not shown) A card slot and an Ir receiver for receiving control signals from the remote controller are provided.

  The control means 20 of the laser projector 10 includes a central control unit 27, an input / output interface 22, a synchronization control unit 31 and the like as shown in FIG. The central control unit 27 controls the operation of each circuit in the laser projector 10, and includes a RAM used as a CPU and work memory, and a ROM that stores operation programs such as various settings in a fixed manner. Has been.

  The image signal input from the input / output connector unit 21 is converted into an image signal of a predetermined format suitable for display by the image conversion unit 23 via the input / output interface 22 and the system bus (SB). After that, it is sent to the central control unit 27. In addition, the CPU of the central control unit 27 receives the image signal as the input signal and the distance data to the screen 9, and the signal transmission time interval to each projection device 1 and each projection device 1 And the projection signal calculated by the CPU is stored in the RAM of the central control unit 27.

  The distance data from the laser projector 10 to the screen 9 is calculated by the distance calculating unit 33. The distance calculating unit 33 reflects the light reflected from the light receiving element of the distance measuring device 50 shown in FIG. Computation means for measuring the distance to a plurality of points on the screen 9 from the electrical signal obtained by receiving and converting the light and calculating the average distance from the screen 9 is provided. Although the distance can be automatically calculated by providing the distance measuring device 50 and the distance calculating unit 33, the user can adjust the focus of the display screen without the distance measuring device 50 and the distance calculating unit 33. It is good also as selecting manually.

  Then, the projection signal stored in the RAM is output to the synchronization control unit 31, and the projection signal is branched by the synchronization control unit 31, and the projection signal of each projection device 1 is calculated at predetermined different time intervals calculated by the central control unit 27. It is sent to the projection device control means 2.

  Each projection device control unit 2 to which a projection signal is input from the synchronization control unit 31 includes a projection device control unit 3, a motor control circuit 4, an encoder 5, and the like. This projection device control unit 3 sends a signal of intensity, hue, and change with time according to the projection signal to the laser light emitter 8 which is a light source device, and also outputs the projection signal and a later-described motor control circuit 4 for controlling the scanning means. A control signal based on the angle data is sent.

  This scanning means comprises a galvanometer mirror 7 which is a reflection means which can be driven in a two-dimensional direction, and a motor 6 which is a drive source of the galvanometer mirror 7. The projection device control means 2 controls the scanning means via the laser light emitter 8 and the motor control circuit so that the laser beam emitted from the laser light emitter 8 is scanned in a two-dimensional direction by the galvanometer mirror 7. The image is displayed on the screen 9.

  The motor control circuit 4 generates a current for driving the motor 6 based on the supplied control signal, and drives the motor 6 by supplying a current to the motor 6. Two motors 6 are installed with respect to the galvanometer mirror 7. The galvanometer mirror 7 is held on two orthogonal axes, and the motors are directly connected to the two axes, respectively. It can be driven in the direction.

  The encoder 5 detects angle data in the two-dimensional direction of the galvanometer mirror 7, and this angle data is sent to the projection device control unit 3. The encoder 5 may be of any system such as an absolute system or an incremental system.

  Further, the image compression / decompression unit 28 of the projector control means 20 sequentially compresses the luminance signal and color difference signal of the image signal by processing such as ADTC and Huffman coding, and sequentially applies them to a memory card 30 which is a detachable recording medium. In the recording process to be written and in the playback mode, the image data recorded on the memory card 30 is read, the individual image data constituting a series of moving images is decompressed and sent to the central control unit 27 via the image conversion unit 23, and stored in the memory. A moving image or the like can be displayed based on the image data stored in the card 30.

  In addition, the operation signal of the key / indicator unit 29 composed of keys and indicators provided on the top plate 11 of the main body case is directly sent to the central control unit 27, and the key operation signal from the remote controller is received by Ir. The code signal received by the unit 25 and demodulated by the Ir processing unit 26 is sent to the central control unit 27.

  The central control unit 27 is connected to a sound processing unit 24 via a system bus (SB). The sound processing unit 24 includes a sound source circuit such as a PCM sound source, and the sound data is analog in the projection mode and the reproduction mode. Thus, the loudspeaker 32 can be driven to emit loud sounds.

  As shown in FIG. 1, the first to third projection devices 1a, 1b, and 1c arranged in the laser projector 10 have the central optical axis X of the first to third projection devices 1a, 1b, and 1c. They are arranged in parallel so as to be parallel to each other. By arranging in parallel in this way, as shown in FIG. 3, the first to third scannable regions 40a, 40b, and 40c are virtually parallel to the left and right by a predetermined distance on the screen 9 arranged in front. To be determined. Then, the projection area 41 of each projection apparatus 1 is determined based on the aspect ratio of the display screen to be projected in the overlapping part of the first to third scannable areas 40a, 40b, 40c.

  Further, since the scannable area 40 and the projection area 41 depend on the distance between the laser projector 10 and the screen 9, as described above, the distance can be adjusted by the distance measurement device 50 and the distance calculation unit 33 or the user's focus adjustment. This is calculated and determined by the central control unit 27 to which the data is input. In the projection area 41, the ratio of the projection area 41 to the scannable area 40 increases as the distance between the laser projector 10 and the screen 9 increases.

  Then, as shown in FIG. 4, when the vertical width and the horizontal width of the projection area 41 are determined, the projection point 42 formed by scanning of the laser beam from the projection apparatus 1 in the projection area 41 by the projection apparatus control unit 3. The operation speed and the scanning trajectory 43 at each coordinate position of the galvanometer mirror 7 are determined by calculating the distance between the projection point 42 and the projection point 42.

  When raster scanning is performed on the screen 9, the projection time of the projection signal is set so that the projection point 42 formed by the laser beam emitted from each projection apparatus 1a, 1b, 1c in the central control unit 27 is at a different position. The interval is calculated, and the synchronization control unit 31 to which the projection signal and the transmission time interval data are input branches the projection signal to each projection device control means 2 and sequentially transmits it at different time intervals.

  This transmission time interval is the coordinate position of the projection point 42 formed by the laser beam emitted from the first projection device 1a and the coordinate position of the projection point 42 formed by the laser beam emitted from the second projection device 1b. And the coordinate position of the projection point 42 formed by the laser beam emitted from the third projection device 1c is determined so as to be substantially equidistant. Note that the relationship with the coordinate position of the projection point 42 is not limited to equal intervals, but may be unequal intervals.

  Each projection device control means 2 then projects a specific pixel formed by scanning the laser beam from the first to third projection devices 1a, 1b, 1c at the coordinate positions of all the projection points 42 on the same scanning trajectory 43. The scanning means and the laser emission so that the coordinate positions of the points 42 coincide with each other and the respective scanning points by the laser beams from the first to third projection devices 1a, 1b, 1c are different coordinate positions at the same time. To control the device 8. As a result, the projection point 42 formed by the scanning of the laser beam from the first to third projection devices 1a, 1b, 1c is formed at the same coordinate position, but at the same time, it is displayed at the shifted coordinate position. Will be.

  Projection points 42 formed by scanning the laser beam emitted from the first projection device 1a are sequentially formed on the scanning trajectory 43 on the screen 9. Specifically, the laser beam is scanned by rotating the galvanometer mirror 7 in the right direction with the uppermost step at the left end of the projection area 41 as the scanning start point. When the laser beam reaches the end point of the linear scanning range, the direction is changed and one step lower Returning to the left end, which is the starting point of the straight line scanning range, scanning in the right direction is repeated in the same manner, and scanning is performed to the lowest level, thereby forming a projection point 42 at each coordinate position. Then, when the laser beam is scanned to the lowest level, it returns to the uppermost level at the left end of the projection area 41 based on the projection signal to be displayed on the screen next, and is scanned again.

  In addition, the second projection device 1b is arranged on the same scanning trajectory 43 as the first projection device 1a so that the projection points 42 are formed at the same coordinate positions as the projection points 42 displayed by the first projection device 1a. The scanning is performed with a slight delay with respect to the scanning of the first projection device 1a. The third projection device 1c is scanned with a slight delay with respect to the scanning of the second projection device 1b. As a result, the projection points 42 formed by scanning the laser beams from the respective projectors 1a, 1b, 1c are sequentially formed without overlapping.

  In this way, a plurality of projection apparatuses 1 are provided, and each projection apparatus 1 is arranged in parallel so that the central optical axes X of the respective projection apparatuses 1 are parallel to each other, and a scanable area on the screen of each projection apparatus 1 In the projection region 1 in the overlapping portion of 40a, 40b, and 40c, the laser beam is scanned synchronously, thereby suppressing the output of the projection device 1 per one and improving the reliability, and a plurality of projection devices of the same specification 1 can be used to delay the projection signal and branch and send it to each projection device 1, so that each projection device 1 can easily display a clear image on the screen 9 without performing different controls. The projector 10 can be provided.

  Further, by controlling the scanning of each projection device 1 at different time intervals, the laser beams emitted from the projection devices 1 do not overlap each other, and the laser projector 10 with higher safety can be provided.

  Furthermore, by providing the distance measuring device 50, even if the distance to the screen 9 changes, the projection area 41 can be determined by automatically calculating the distance, and an image resulting from the distance to the screen 9 can be obtained. Therefore, it is possible to provide a laser projector 10 that can be used without being limited to the projection location and the installation location of the laser projector 10.

  The present invention is not limited to the above-described embodiments, and can be freely changed and improved without departing from the gist of the invention. For example, as described above, not only the case where scanning is performed within the projection region 41 in the overlapping portion of the scannable region 40 of each projection device 1, but also the entire scannable region 40 of each projection device 1 is shown in FIG. The galvanometer mirror 7 may be driven and controlled so that scanning can be performed within the range. That is, the first projection device 1a scans in the entire range of the first scannable region 40a, the second projection device 2a scans in the entire range of the second scannable region 40b, and the third projection device 1c Scanning is performed over the entire range of the third scannable region 40c.

  In this case, the projection device control unit 3 of each projection device control means 2 has an appropriate intensity from the laser emitter 8 only at each coordinate position on the scanning trajectory 43 in the projection region 41 determined by the central control unit 27, The projection point 42 is formed in the projection region 41 by emitting the hue laser beam.

  As a result, it is not necessary to change the operation of the galvanometer mirror 7 according to the distance to the screen 9, and even if the distance changes, the galvanometer mirror 7 performs the same operation, and the laser beam emission time interval by the laser emitter 8 Therefore, it is only necessary to control the above and the like, so that the drive control of the scanning means can be easily performed.

  Further, the projection apparatuses 1 are not limited to the case where they are arranged side by side in the left-right direction, and as shown in FIG. The projection region 41 may be formed in the overlapping portion of the scannable region 40 by arranging them in parallel so that X is parallel. Thus, by arranging each projection device 1, the ratio of the projection region 41 to the scannable region 40 can be increased.

1 is a perspective view showing an external appearance of a projector according to an embodiment of the invention. FIG. 3 is a diagram illustrating a functional circuit block of the projector according to the embodiment of the invention. FIG. 5 is a diagram showing a scannable area and a projection area of the projector according to the embodiment of the invention. FIG. 4 is a diagram illustrating a scanning trajectory of the projector according to the embodiment of the invention. FIG. 4 is a diagram illustrating a scanning trajectory of the projector according to the embodiment of the invention. FIG. 5 is a diagram showing a scannable area and a projection area of the projector according to the embodiment of the invention.

Explanation of symbols

1 Projector 1a First projector
1b Second projector 1c Third projector
2 Projector control means 3 Projector controller
4 Motor control circuit 5 Encoder
6 Motor 7 Galvano mirror
8 Laser emitter 9 screen
10 Laser projector 11 Top plate
12 Front panel 13 Various terminals
14 Projection port 20 Projector control means
21 I / O connector 22 I / O interface
23 Image converter 24 Audio processor
25 Ir receiver 26 Ir processor
27 Central control unit 28 Image compression / decompression unit
29 Key / indicator section 30 Memory card
31 Sync control unit 32 Speaker
33 Distance calculator 40 Scannable area
40a First scannable area 40b Second scannable area
40c Third scannable area 41 Projection area
42 Projection point 43 Scanning trajectory
50 Distance measuring device
X Center optical axis of the projector

Claims (3)

Projector control means for generating a projection signal based on a predetermined input signal;
A plurality of projection devices that display images by scanning the screen with light rays based on the projection signals;
The projector control means includes a synchronization control unit that branches the projection signal and sends it to each projection device,
Each of the projection devices includes a light source device that emits a light beam, a scanning unit that scans the light beam emitted from the light source device, a projection device control unit that controls the scanning unit in a scannable area on the screen, With
The projection devices are arranged side by side so that the central optical axes of the projection devices are parallel to each other, and in the overlapping area of the scannable areas of the projection devices, the light beams are scanned synchronously, thereby A projector characterized by displaying an image on the screen.   The synchronization control unit sends the projection signals to the projection devices at predetermined different time intervals so that a position of a projection point formed by scanning a laser beam which is one of the light beams from the projection devices is shifted. The projector according to claim 1, wherein the projector is sent to the projector. 2. The apparatus according to claim 1, further comprising: a distance measuring device, wherein the projector control unit includes a distance calculating unit that calculates a distance from the screen, and determines an overlapping portion of the scannable region based on the distance from the screen. Alternatively, the projector according to claim 2.

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