JP2005338652A - Light source device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light source device which is compact and has small power consumption and is easily synchronized with a display device. <P>SOLUTION: A light source device 3 comprises an R color LED 12, G color LED 13, a B color LED 14, reflectors 15, 16, and 17, a holding member 18 for holding the color LEDs 12, 13, and 14 and reflectors 15, 16, and 17, a hollow motor 19 for rotating the holding member 18, a motor control part 20 for controlling the hollow motor 19, and a motor driver 21. Primary color light is radiated to an incidence surface 4a of a condenser lens 4 from the color LEDs 12, 13, and 14. A reflective liquid crystal panel 6 is driven synchronously with rotation of the color LEDs 12, 13, and 14 and modulates incident primary color light into primary color image light. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a light source device that sequentially enters a plurality of types of colored light having different colors into an illumination optical system.

  A projector that displays a color image on a screen by a projection lens is known. The projector includes a three-plate type projector using three display devices corresponding to each primary color light of red light, green light, and blue light (hereinafter, R light, G light, B light), and one display device. There is a single plate type. A single-plate projector is equipped with a light source device that sequentially emits each primary color light, irradiates each primary color light sequentially to the display device to produce primary color image light, and switches this primary color image light on the screen at high speed. A time-division format that is recognized as a color image is known.

  2. Description of the Related Art As a light source device used in a time-sharing projector, a device using a filter disk in which a plurality of color filters that transmit only primary color light are arranged in a rotation direction is well known. By rotating the filter disk so as to cross the optical path of white light emitted from the light source, each primary color light can be sequentially emitted in synchronization with the rotation of the filter disk.

  As a light source device that does not use a filter disc, for example, the light source devices described in Patent Documents 1 and 2 are known. In these patent documents, LED arrays emitting primary light of R light, G light, and B light are arranged on the three incident surfaces of the cross dichroic prism, and each primary color light is sequentially emitted from the exit surface of the cross dichroic prism. A light source device is described. Each primary color light is irradiated to the display device, and the display device modulates each primary color light in synchronization with the blinking timing of each LED array.

JP 2003-339052 A JP 2003-186110 A

  However, in a light source device using a filter disk, a light source that emits white light and an optical system that condenses the white light emitted from the light source must be disposed upstream of the filter disk. As a result, the light source device is increased in size in the light irradiation direction, and there are problems that the number of components increases. Further, as a light source that emits white light, an ultra-high pressure mercury lamp, a metal halide lamp, a xenon lamp, a halogen lamp, or the like is generally used, and there is a problem that power consumption is large.

  In addition, the light source devices described in Patent Documents 1 and 2 have a problem that it is difficult to adjust the blinking timing of each LED array and the drive timing of the display device. Even if these timings are shifted slightly, the image quality deteriorates, so that it is necessary to control each LED array and display device more accurately, resulting in an increase in manufacturing cost.

  An object of the present invention is to provide a light source device that is compact and easy to synchronize with a display device.

  The present invention relates to a light source device that sequentially enters a plurality of types of colored light having different colors into an illumination optical system, and a plurality of types of light emitters that respectively emit the plurality of types of colored light, and rotatable about a predetermined axis. A holding member that is supported and holds the plurality of types of light emitters arranged around the axis; and a driving unit that continuously rotates the holding member; Each light emitter is sequentially moved to a position where the emitted colored light is rotated integrally with the holding member and incident on the illumination optical system.

  Preferably, the driving means is a motor, and the holding member rotates integrally with a rotor of the motor. Moreover, it is preferable that the holding member includes a reflector that collects and emits color light from each light emitter. Further, the plurality of types of light emitters are preferably light emitting diodes having different emission colors.

  The color light emitted from the illumination optical system is applied to a display device that sequentially displays images according to the type of color light in synchronization with the rotation of the motor, and the light source device of the present invention is used for a projector or the like. Is preferred.

  According to the present invention, it is possible to provide a light source device that is compact and can be easily synchronized with a display device. Further, by using a light emitting diode as a light source, power consumption can be reduced and heat generation can be suppressed.

  As shown in FIG. 1, the projector 2 includes a light source device 3, a condensing lens 4, a PBS (Polarization Beam Splitter) prism 5, a reflective liquid crystal panel 6, a projection lens 7, and a screen 8.

  As shown in FIG. 2, the light source device 3 includes an R color light emitting diode 12 that emits R light, a G color light emitting diode 13 that emits G light, and a B color light emitting diode 14 that emits B light (hereinafter referred to as R color LEDs 12 and G, respectively). Color LED 13, B color LED 14), reflectors 15, 16, 17, holding members 18 for holding the respective color LEDs 12, 13, 14 and reflectors 15, 16, 17, a hollow motor 19 for rotating the holding member 18, and hollow A motor control unit 20 (see FIG. 1) for controlling the motor 19 and a motor driver 21 (see FIG. 1) are included.

  Electric power is supplied to each color LED 12, 13, 14 from a terminal 24 in contact with the positive electrode 22 and a terminal 25 in contact with the negative electrode 23. Each of the electrodes 22 and 23 is formed in an annular shape and is attached to a shaft 26 fixed to a casing (not shown) of the projector 2. The terminal 24 is biased toward the positive electrode 22, and the terminal 25 is biased toward the negative electrode 23. When the LEDs 12, 13, 14 and the holding member 18 are rotated, the terminals 24, 25 are moved toward the electrodes 22, 23. Rotates while touching. In the drawing of this example, each color LED 12, 13, and 14 is one, but a plurality of each may be provided according to the required light quantity.

  Each reflector 15, 16, 17 is formed in a parabolic shape and is provided corresponding to each color LED 12, 13, 14. Each reflector 15, 16, 17 reflects part of the illumination light emitted from each color LED 12, 13, 14 in a direction substantially perpendicular to the rotation direction.

  The holding member 18 is formed in a columnar shape, and holds the LEDs 12, 13 and 14 arranged around the rotation axis 33. The holding member 18 is provided with a space (not shown) through which the shaft 26 passes.

  The hollow motor 19 is a brushless DC motor composed of a rotor 27 and a stator 28. The rotor 27 includes a rotor main body 29 formed in a substantially cylindrical shape and permanent magnets 31 provided on the outer peripheral surface 29a of the rotor main body 29 at predetermined intervals. The stator 28 includes a stator body 30 formed in a substantially cylindrical shape, windings (not shown) provided near the inner peripheral surface 30a of the stator body 30, and magnetic elements (for example, hall elements) (shown). None).

  A bearing 32 in contact with the inner peripheral surface 30a of the stator main body 30 is provided on the outer peripheral surface 29a of the rotor main body 29 so that the rotor 27 can rotate smoothly. The bearing 32 may be provided on the inner peripheral surface 30 a side of the stator body 30. Further, the rotor 27 is formed with a hollow portion 34 penetrating along the rotation axis 33.

  In the light source device 3, the outer peripheral surface 18 a of the holding member 18 and the inner peripheral surface 29 b of the rotor 27 of the hollow motor 19 are fixed, the holding member 18 is disposed in the hollow portion 34, and the shaft 26 is disposed inside the holding member 18. It is assembled by arranging. The assembled light source device 3 is shown in FIG. In the light source device 3, the shaft 26 and the stator 28 of the hollow motor 19 are fixed to the housing (not shown) of the projector 2, and each color LED 12, 13, 14, the holding member 18 and the rotor 27 are integrally displaced. It is arranged to become. In this example, the holding member 18 and the rotor 27 are formed separately, but the holding member 18 and the rotor 27 may be integrally formed.

  The motor control unit 20 (see FIG. 1) and the motor driver 21 (see FIG. 1) control the driving of the hollow motor 19. When the rotor 27 rotates with respect to the stator 28, a magnetic element (not shown) provided in the stator body 30 detects the position of the permanent magnet 31 of the rotor body 29 and sends a detection signal to the motor controller 20. send. The motor control unit 20 calculates the rotation position and rotation speed of the rotor 27 from this detection signal, and sends a drive signal to the motor driver 21 based on the calculation result. The motor driver 21 gives the current and voltage calculated from the drive signal from the motor control unit 20 to the windings (not shown) of the stator 28. As a result, the rotor 27 is given a rotational force and continues to rotate at the set rotational speed. As the rotor 27 rotates, the color LEDs 12, 13, 14 and the holding member 18 integrated with the rotor 27 also rotate. Since the rotor 27 of the hollow motor 19 rotates stably with respect to the stator 28, the LEDs 12, 13, 14 and the holding member 18 also rotate stably.

  According to the above configuration, the light source device 3 can be made compact. Further, by using a light emitting diode as a light source, power consumption can be reduced and heat generation can be suppressed.

  As shown in FIG. 1, the condenser lens 4 is disposed away from the rotation axis 33 on the downstream side in the light traveling direction of the light source device 3. In the condenser lens 4, when the respective color LEDs 12, 13, 14 rotate, the primary color light irradiation areas emitted from the respective color LEDs 12, 13, 14 sequentially pass through the incident surface 4 a of the condenser lens 4. It will be arranged at the correct position. The condensing lens 4 condenses the primary color lights sequentially irradiated on the incident surface 4 a and sequentially irradiates the incident surface 5 a of the PBS prism 5 arranged on the downstream side of the condensing lens 4.

  The PBS prism 5 has two prisms 38 and 39 each having a right-angled isosceles triangle, with the inclined surfaces facing each other and a reflective polarizing layer 40 having a Brewster angle of 45 ° sandwiched therebetween. Is. Of the light incident at 45 °, the reflective polarizing layer 40 transmits P-polarized light and reflects S-polarized light. Therefore, among the light incident from the incident surface 5a, the P-polarized light is transmitted through the reflective polarizing layer 40 and emitted from the output surface 5b, and the S-polarized light is reflected by the reflective polarizing layer 40 and emitted from the incident / exit surface 5c.

  The front surface of the reflective liquid crystal panel 6 is arranged to face the incident / exit surface 5 c of the PBS prism 5. The reflective liquid crystal panel 6 modulates incident light for each pixel and reflects it. Here, the incident light corresponding to the bright display pixel is reflected as P-polarized light by rotating the polarization direction by 90 °, and the incident light corresponding to the dark display pixel is reflected as S-polarized light without changing the polarization direction. The The reflective liquid crystal panel 6 is provided with an electrode corresponding to each pixel, and the polarization direction of incident light can be changed by applying a voltage to the electrode. A voltage is applied to each electrode by a panel control unit (not shown) based on the image data. The panel control unit is driven in synchronization with the rotation of the respective color LEDs 12, 13 and 14 of the light source device 3.

  The reflected light, which is a mixture of P-polarized light and S-polarized light, enters the PBS prism 5 from the incident / exit surface 5 c and proceeds to the reflective polarizing layer 40. The P-polarized light passes through the reflective polarizing layer 40 and then exits the PBS prism 5 and enters the projection lens 7. The S-polarized light is reflected by the reflective polarizing layer 40 and then exits the PBS prism 5 and proceeds to the light source device 3. .

  The projection lens 7 projects the light emitted from the PBS prism 5 onto the screen 8.

  Below, the effect | action by the said structure is demonstrated. The respective color LEDs 12, 13, 14 and the holding member 18 rotate at a high speed at a constant speed under the control of the motor control unit 20 and the motor driver 21. Each color LED 12, 13 and 14 is continuously lit and emits primary color light at all times. The irradiation area of each primary color light emitted from each color LED 12, 13, 14 sequentially passes through the incident surface 4 a of the condenser lens 4 as the respective color LEDs 12, 13, 14 rotate. Thereby, on the incident surface 4a of the condensing lens 4, the color of illumination light is sequentially switched at high speed in the order of R light, G light, and B light.

  The primary color lights sequentially irradiated on the incident surface 4 a of the condenser lens 4 are condensed and converted into primary color image lights through the PBS prism 5 and the reflective liquid crystal panel 6. Here, the reflective liquid crystal panel 6 is driven to modulate each incident primary color light in synchronization with the rotation of the respective color LEDs 12, 13, 14. Each primary color image light is projected on the screen 8 through the projection lens 7. On the screen 8, each primary color image light is switched at a high speed and recognized as a color image.

  In the above-described embodiment, the R color LED, the G color LED, and the B color LED are used as the light source of the light source device. However, a color light other than the three primary colors, for example, an LED that emits white light may be added. Good. Moreover, what uses light sources other than LED may be used.

  In the above embodiment, the brushless DC motor is used as the hollow motor, but instead, a motor such as a DC servo motor, a synchronous motor, or an induction motor may be used.

  In the above embodiment, the PBS prism and the reflective liquid crystal panel are used, but a TIR prism and DMD may be used instead. Even in this case, it is the same that the DMD is driven in synchronization with the rotation of each color LED and the primary color light incident on the DMD is modulated.

  In the above embodiment, each primary color light emitted from the light source device directly enters the condenser lens. However, each primary color light emitted enters the condenser lens after passing through an optical member such as a mirror. It is good as well.

  Further, any configuration may be used as long as the positions of the respective color LEDs are sequentially moved so that the respective primary color lights are sequentially guided to the condensing lens.

1 is a schematic perspective view of a projector using a light source device according to an embodiment of the present invention. It is a disassembled perspective view of a light source device. It is a perspective view of a light source device.

Explanation of symbols

3 Light source device 6 Reflective liquid crystal panel 12 R color LED
13 G LED
14 B color LED
18 Holding member 19 Hollow motor 33 Rotating axis 34 Hollow part

Claims (5)

In a light source device that sequentially enters a plurality of types of colored light having different colors into an illumination optical system, the plurality of types of colored light that respectively radiate the plurality of types of colored light, and supported rotatably around a predetermined axis, A holding member that holds a plurality of types of light emitters arranged around the axis, and a driving unit that continuously rotates the holding member;
The light source device characterized in that the plurality of types of light emitters are rotated integrally with the holding member while being lit, and the light emitters are sequentially moved to positions where the emitted colored light is incident on the illumination optical system. .   The light source device according to claim 1, wherein the driving unit is a motor, and the holding member rotates integrally with a rotor of the motor.   The light source device according to claim 1, wherein the holding member includes a reflector that collects and emits colored light from each light emitter.   4. The light source device according to claim 1, wherein the plurality of types of light emitters are light emitting diodes having different emission colors. 5. The color light emitted from the illumination optical system is applied to a display device that sequentially displays images according to the type of color light in synchronization with rotation of the motor. The light source device described.

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