JP2002122807A - Projection type display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the number of parts and to make the diameter of a rotary color filter small. SOLUTION: This display device is constituted of a light source 1, a rotary filter unit 9a, a light valve 12, a sensor 4a sensing the rotation of the unit 9a from the optical characteristic of each color filter 91a, a light valve driving circuit 5 driving the light valve 12 in order to modulate the colored light from the unit 9a with output from the sensor 4a as a reference signal, and a projection lens 14 enlarging and projecting a picture formed in the picture display area of the light valve 12. A reference mark 93 sticking area is not needed and the compact and low-cost rotary filter unit 9a is used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a projection display device that uses a rotating color filter to enlarge and project an image on a light valve onto a screen.

[0002]

2. Description of the Related Art FIG. 9 is an explanatory view of a conventional projection display device. The projection display apparatus includes a light source 1, an optical sensor 4, a light valve driving circuit 5 for outputting a driving signal of the light valve 12 in phase with a sensor output, and a light-transmitting glass or the like. , A lens unit 7 also made of glass or the like, a rotary filter unit 9 having a plurality of color filters 91 and rotated by a motor 92, and a light valve driving circuit 5. A light valve 12 that forms an image in accordance with a drive signal given from the camera, a prism 13 that bends an illumination light beam, a projection lens 14, and a screen 15. The image on the light valve 12 is enlarged and projected on the screen 15. It has become. In addition, the code | symbol 2 in FIG. 9 has shown the light source emission light, and the code | symbol 16 has shown the observer, respectively.

Here, as the light source 1, for example, a discharge lamp such as a metal halide lamp or a xenon lamp, or a halogen lamp is used. In a projection display device, a light valve includes a liquid crystal panel (LCD),
l Micromirror Device (DMD), Thin-Film Micromi
rror Array (TMA), Image light Amplifier (IL
A), Grating Light Valve (GLV) and the like are applied.

Further, the conventional rotary filter unit 9 includes:
As shown in FIG. 10, it is formed in a disk shape, and its circumferential portion is a translucent color filter 91 (typically, red (R) / green (G)).
/ Blue (B) angle division filter), and the central part is opaque at the non-reference mark 93 and the reference mark 9.
4 are formed.

[0005] Each color filter 91 transmits the light emitted from the light source 1 and emitted from the light source 1 and changes the color of the transmitted light with the rotation of the rotary filter unit 9 so as to be selected in a time-division manner. The light is focused on the incident end face of the columnar optical element 6 as a colored light flux.

The non-reference mark 93 is formed by, for example, coating the surface of a predetermined disk 93a with a black paint, and has a low light reflectance. On the other hand, the reference mark 94 is set to have a high reflectance with an aluminum tape or the like, and is attached so as to overlap a part of the non-reference mark 93 of the disk 93a. Thereby, the non-reference mark 93
The contrast is formed between the reference mark 94 and the reference mark 94. Then, the optical sensor 4 is configured as shown in FIG.
Is a reflective photo-interrupter having a light-emitting element 41 and a light-receiving element 42. When the rotary filter unit 9 rotates, it detects the passage of the reference mark 94 and generates a reference signal in synchronization with the detection. Has become.

Next, the operation of the conventional projection display device will be described. The condensed light beam 2 is emitted from the light source 1 toward the color filter 91 of the rotary filter unit 9, and the rotary filter unit 9 is rotated by the motor 92. Light source 1
Condensed light flux 2 emitted from the rotating color filter 91
(Red (R) / Green (G) / Blue (B) angle division filter)
And is condensed on the incident end face (lower face) of the columnar optical element 6 as a light flux selectively colored in a time division manner, guided inside, and emitted from the exit end face. The light emitted from the columnar optical element 6 is condensed by the lens means 7, its direction is bent by the prism 13, and
The second image display area is illuminated.

At the same time as these operations, the optical sensor 4
The light emitted from the light emitting element 41 in FIG.
The non-reference mark 93 or the reference mark 94 is irradiated.
Since the reflectance of the non-reference mark 93 is set to be low and the reflectance of the reference mark 94 is set to be high, the light reflected from the reference mark 94 is received by the light receiving element 42 and the light valve is transmitted from the sensor 4 in synchronization with the light. The reference signal is output to the drive circuit 5.

The light valve drive circuit 5 outputs a drive signal to the light valve 12 at a timing synchronized with the reference signal given from the sensor 4. The light valve 12 forms an image in the image display area based on the drive signal.

As described above, the light passing through each color filter 91 of the rotary filter unit 9 is applied to the image display area of the light valve 12 via the columnar optical element 6, the lens means 7 and the prism 13, and is synchronized with the light. Then, the light valve driving circuit 5 drives and controls the image of the light valve 12 at the timing when the sensor 4 detects the passage of the reference mark 94 of the rotary filter unit 9, so that the image display area of the light valve 12 is irradiated. The timing of irradiation light and the timing of forming an image to be formed on the light valve 12 can be easily synchronized. FIG. 12 is a timing chart showing the relationship between the light L01 emitted from the prism 13 to the image display area of the light valve 12 and the reference signal L02. In this conventional example, the light L0 radiated from the prism 13 to the image display area of the light valve 12 is
1 is synchronized with the reference signal L02.
In the light L01 emitted from the prism 13 to the image display area of the light valve 12, reference symbol R in FIG. 12 indicates red light, reference symbol G indicates green light, and reference symbol B indicates blue light.

In this manner, an image is formed on the light valve 12, and a light beam relating to the image is transmitted forward through the prism 13 and projected on the screen 15 by the projection lens 14. 16 (for details of the projection type display device using the DMD, see L.
A. Yoder, “Digital Light Processing: Spanning the Di
splay Industry with Digital Solutions ”, LCD / PDP I
nternational '98 (1998), for details of a projection display device using a GLV element, see DMBloom, "The Grati.
ng Light Valve: revolutionizing display technolog
y ", SPIE Vol. 3013, pp-165-171, (1997)).

[0012]

In the conventional projection type display device, it is necessary to form a non-reference mark 93 and a reference mark 94 at the center of the rotary filter unit 9, so that the diameter of the rotary filter unit 9 can be reduced. Had been restricted.

The non-reference mark 93 and the reference mark 9
For the formation of the reference mark 4, first, the surface of the disk 93 a is painted with black paint or the like, and then the reference mark 94 is formed using an aluminum tape or the like, and the remaining portion is formed of the non-reference mark 93.
However, since such operations such as painting and attaching tapes are involved, the manufacturing process is complicated, and this has been a factor of increasing the component cost and the manufacturing price of the projection display device.

Further, the black paint as the non-reference mark 93 having a low reflectance absorbs light, which causes a rise in the temperature of the device.

SUMMARY OF THE INVENTION In view of the above problems, it is an object of the present invention to provide a compact projection display device in which the number of parts is reduced, the temperature rise is suppressed, and the diameter of the rotary color filter is reduced.

[0016]

According to a first aspect of the present invention, there is provided a rotary filter unit comprising a light source, and a plurality of color filters for selectively coloring outgoing light from the light source in a time-division manner; A light valve illuminated by the emitted light colored by a color filter, a sensor for sensing rotation of the rotary filter unit based on time-division selective coloring of the color filter, and a signal provided from the sensor. A light valve drive circuit for driving the light valve for image formation; and projection lens means for enlarging and projecting an image formed in an image display area of the light valve.

According to a second aspect of the present invention, there is provided the projection display apparatus according to the first aspect, wherein the sensor includes a light emitting element and a light receiving element which are arranged to face each other at a predetermined interval,
A peripheral portion of the color filter is rotatably inserted into the space.

According to a third aspect of the present invention, there is provided the projection display apparatus according to the second aspect, wherein a slit is arranged at least on a light receiving surface side of the light receiving element.

According to a fourth aspect of the present invention, in the projection display device according to the third aspect, when the light receiving area of the light receiving element is φ, the width w of the slit is “φ / w> 3 "
It is what becomes.

According to a fifth aspect of the present invention, there is provided the projection type display device according to the first aspect, wherein the sensor includes a light emitting element and a light receiving element which are arranged adjacent to each other, and faces the light emitting element and the light receiving element. The peripheral portion of the color filter is rotatably arranged.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 is a block diagram showing a projection display device according to Embodiment 1 of the present invention, FIG. 2 is a schematic diagram showing a configuration of a main part of a rotary filter unit, and FIG.
4 and 4 are schematic diagrams showing the configuration of an optical sensor.
Elements having the same functions as in the conventional example are denoted by the same reference numerals.

In this projection type display device, as shown in FIG. 1, the reference mark 94 and the non-reference mark 93 applied in the conventional example are not formed in the rotary filter unit 9a, and any of the color filters 91a is used for the sensor 4a. The sensor 4a detects whether or not it has passed the detection position based on the color change, thereby omitting the conventional disk 93a on which the reference mark 94 and the non-reference mark 93 are formed.

The rotary filter unit 9a includes a translucent fan-shaped red translucent portion R1, a green translucent portion G1, and a blue translucent portion B1 each serving as a color filter 91a along a rotational direction (circumferential direction) P. The rotary filter unit 9a is arranged so as to be adjacent to the rotary filter unit 9a.
Is rotated in the rotation direction P, so that the sensor 4a can detect a color change of the color filter 91a.

The sensor 4a is a transmissive photo-interrupter. A light emitting element 41 and a light receiving element 42 are installed in a light emitting section 45 and a light receiving section 46 of a package 44 having a concave shape in side view as shown in FIG. 41 and 42 are arranged to face each other with a light transmitting space 47 between the light emitting unit 45 and the light receiving unit 46 interposed therebetween. Light emitting section 45 of package 44
In the light receiving section 46, each lens section (light emitting area and light receiving area) 41a, 42a of each element 41, 42 is provided.
Vertical slit 43 to face 7 (see FIG. 4)
Are formed. This slit 43 is
The width w of the slit 43 is 1 to the diameter φ of the lens portions 41a and 42a of the elements 41 and 42.
/ 3, so that the directivity of the light beam is sufficiently ensured, and the mixing of the scattered light component due to the boundary between the light transmitting portions R1, G1, and B1 as the color filter 91a is suppressed. I can do it.

The rotary filter unit 9 is disposed in a light-transmitting space (interval) 47 between the light emitting section 45 and the light receiving section 46.
By loosely inserting the circumference of “a”, the light emitted from the light emitting element 41 passes through each color filter 91 a and reaches the light receiving element 42. Incidentally, reference numeral 4 in FIGS.
Reference numerals 8 and 49 denote lead wires for external drawing.

The light receiving element 42 is provided with a red light transmitting portion R1.
The reference signal is output to the light valve drive circuit 5 only when the red light corresponding to the above is received.
The light emitted from the light emitting element 41 may be any light such as white light as long as the light includes a red wavelength component.

The other structure is the same as that of the conventional example. In particular, the light valve driving circuit 5 drives the light valve 12 based on the reference signal from the sensor 4a. The point at which the passed light is applied to the image display area of the light valve 12 via the columnar optical element 6, the lens means 7 and the prism 13, and the light flux related to the image formed on the light valve 12 is
This is the same as the conventional example in that the light is transmitted forward and is projected forward and projected on the screen 15 by the projection lens 14.

The operation of the projection display device having the above configuration will be described.

First, the condensed light beam 2 is emitted from the light source 1 toward the rotary filter unit 9a,
To rotate the rotary filter unit 9a. The condensed light beam 2 emitted from the light source 1 is transmitted through one of the rotating color filters 91a, and is condensed on the incident end face of the columnar optical element 6 as a time-divisionally colored light beam. Such light is guided inside the columnar optical element 6 and emitted from the emission end face. The light emitted from the columnar optical element 6 is condensed by the lens means 7 and bent by the prism 13 to illuminate the image display area of the light valve 12.

At the same time as the above operation, the optical sensor 4a
The light emitted from the light emitting element 41 in the inside passes through the circumference of the color filter 91a of the rotary filter unit 9a inserted into the light transmitting space 47 interposed between the light emitting part 45 and the light receiving part 46, and the light receiving element Reach 42.

The light receiving element 42 receives red light corresponding to the red light transmitting portion R1 as the color filter 91a as shown in FIG. 5 based on the optical characteristics (eg, wavelength characteristics) of the received light. , A high-active reference signal is output to the light valve drive circuit 5. In FIG. 5, reference symbol R denotes a red light receiving period, reference symbol G denotes a green light receiving period, and reference symbol B denotes a blue light receiving period.

The light valve drive circuit 5 outputs a drive signal to the light valve 12 at a timing synchronized with the reference signal given from the sensor 4a. The light valve 12
An image is formed in the image display area based on the drive signal.

As described above, the light that has passed through each color filter 91a of the rotary filter unit 9a is reflected by the columnar optical element 6,
Light valve 12 through lens means 7 and prism 13
The light valve drive circuit 5 drives and controls the image of the light valve 12 at the timing when the sensor 4a detects the passage of each color filter 91a of the rotary filter unit 9a in synchronization with the irradiation of the image display area. This makes it possible to easily synchronize the timing of the irradiation light irradiating the image display area of the light valve 12 with the timing of forming the image formed on the light valve 12.

In this manner, an image is formed on the light valve 12, and a light beam relating to the image is transmitted forward through the prism 13 and projected forward on the screen 15 by the projection lens 14. 16 is appreciated.

As described above, since the reference signal is generated from the sensor 4a based on the optical characteristics of each color filter 91a, the reference mark 94 unlike the conventional example is not required, and therefore, the rotary filter unit 9a It is possible to realize a compact projection display device by reducing the diameter of the device.

In addition, since the black paint on the non-reference mark 93 in the conventional example becomes unnecessary, it is possible to suppress a rise in the temperature of the device due to light absorption.

Further, since it is not necessary to apply a black paint and a reference mark, the manufacturing cost can be reduced and the price of the device can be reduced.

Further, the light emitting element 41 to the light receiving element 4
The width w of the slit 43 as a directional window for ensuring the directivity of the light irradiated to the light source 2 is set to 1/3 of the diameter φ of the lens portions (light transmitting / receiving areas) 41a and 42a of the elements 41 and 42.
Since it is set to be less than this, it is possible to sufficiently secure the directivity of the light ray and to suppress the mixing of the scattered light component caused by the boundary between the light transmitting portions R1, G1, and B1 as the color filter 91a. .

It is to be noted that the slit 43 may be formed only on the light receiving portion 46 side. Even in this case, the scattering caused by the boundary between the light transmitting portions R1, G1, and B1 as the color filter 91a. It goes without saying that mixing of light components can be suppressed.

Embodiment 2 FIG. 6 is a schematic diagram showing a projection display device according to Embodiment 2 of the present invention, and FIG. 7 is a schematic diagram showing a sensor. In FIGS. 6 and 7, elements having the same functions as in the conventional example and the first embodiment are denoted by the same reference numerals.

In the first embodiment, the sensor 4b outputs the reference signal based on the color characteristic of the transmitted light after the light has passed through each color filter 91a. As shown in FIG. 6, the apparatus uses, as the sensor 4b, a reflective photointerrupter in which a light emitting element 41 and a light receiving element 42 are arranged adjacent to each other, and based on the color characteristics of the reflected light on the surface of each color filter 91a. 4b
Outputs the reference signal.

The structure of the rotary filter unit 9a is the same as that shown in FIG. 2 described in the first embodiment, and is different from the conventional rotary filter unit 9 in that the reference mark 94 and the non-reference mark 93 are formed. The disk body 93a is omitted, and is therefore formed smaller in diameter than the conventional rotary filter unit 9.

The sensor 4b uses the reflection type photo-interrupter shown in FIG. 7 and has the same configuration as the reflection type photo-interrupter (sensor 4) in the conventional projection display device shown in FIG. I have. Then, the light receiving element 42 of the sensor 4b, based on the optical characteristics (for example, wavelength characteristics) of the received light, as shown in FIG.
When the red light R reflected by the green light transmitting portion G1 or the blue light transmitting portion B1 as a is received, a high signal is output. Therefore, for example, when white light is emitted from the light emitting element 41 and the green light transmitting portion G1 or the blue light transmitting portion B1 as the color filter 91a is opposed to the sensor 4b, the green light transmitting portion G1 or the blue light Since the light reflected by the light transmitting portion B1 includes a red wavelength component, the output of the sensor 4b directed to the light valve driving circuit 5 becomes a high signal based on the red light incident on the light receiving element 42. When the red light transmitting portion R1 as the color filter 91a faces the sensor 4b, the light reflected by the red light transmitting portion R1 hardly contains a red wavelength component. Reference signal (low active signal)
Is output.

The light valve driving circuit 5 drives the light valve 12 based on the reference signal from the sensor 4b, and the light emitted from the light source 1 and passed through the color filters 91a receives the columnar optical element 6, the lens means The point at which the image display area of the light valve 12 is radiated through the prism 7 and the prism 13, and the luminous flux of the image formed on the light valve 12 passes through the prism 13 and is radiated forward. The point configured to be projected above is the same as in the first embodiment and the conventional example.

According to this embodiment, the first embodiment
Needless to say, there is an advantage similar to the above.

[0046]

According to the first aspect of the present invention, since the sensor for sensing the rotation of the rotary filter unit based on the time-division selective coloring of the color filter is arranged, the optical characteristics of the color filter can be improved. The rotation timing of the rotary filter unit can be detected by the sensor on the basis of this, and it is not necessary to form a reference mark on the rotary filter unit as in the related art. Therefore, the diameter of the rotary filter unit can be reduced, and a compact projection display device can be realized. Further, since a black coating as a non-reference mark is not required, a rise in the temperature of the device due to light absorption is suppressed. be able to. Further, since it is not necessary to apply a black paint and a reference mark, the price of the device can be reduced.

According to the second aspect of the present invention, since the light emitting element and the light receiving element are arranged so as to sandwich the color filter, the reference signal can be generated based on the transmission characteristics of the color filter. Therefore, the reference mark is not required, the diameter of the rotary filter unit can be reduced, and a compact projection display device can be realized.

According to the third aspect of the invention, since only the light passing through the slit is received by the light receiving element, the mixing of the scattered light component caused by the boundary between adjacent color filters is suppressed. The detection accuracy of the rotation timing of the rotation filter unit by the sensor can be improved. In particular, according to the invention described in claim 4,
Since the width of the slit is set to be less than one third of the light receiving area of the light receiving element, it is possible to efficiently suppress the scattered light component caused by the boundary between adjacent color filters.

According to the fifth aspect of the invention, the light emitted from the light emitting element is reflected by the color filter, the reflected light is received by the light receiving element, and the light is reflected on the basis of the optical characteristics of the reflected light at that time. Since the sensor detects the rotation timing of the rotary filter unit, a reference mark is not required, the diameter of the rotary filter unit can be reduced, and a compact projection display device can be realized.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a projection display device according to a first embodiment of the present invention.

FIG. 2 is a schematic diagram showing a main configuration of a rotating color filter in the projection display device according to the first embodiment of the present invention.

FIG. 3 is a schematic side view showing a sensor applied to the projection display device according to the first embodiment of the present invention.

FIG. 4 is a schematic diagram showing a light emitting unit of a sensor applied to the projection display device according to the first embodiment of the present invention.

FIG. 5 is a timing chart illustrating a relationship between a color characteristic of light received by a sensor and a reference signal according to the first embodiment of the present invention.

FIG. 6 is a schematic diagram showing a projection display device according to a second embodiment of the present invention.

FIG. 7 is a schematic side view showing a sensor applied to the projection display apparatus according to Embodiment 2 of the present invention.

FIG. 8 is a timing chart illustrating a relationship between a color characteristic of light received by a sensor and a reference signal according to the second embodiment of the present invention.

FIG. 9 is a diagram showing a conventional projection display device.

FIG. 10 is a schematic diagram showing a configuration of a main part of a rotating color filter in a conventional projection display device.

FIG. 11 is a schematic side view showing a sensor applied to a conventional projection display device.

FIG. 12 is a timing chart showing a relationship between a color characteristic of light received by a sensor and a reference signal in a conventional projection display device.

[Explanation of symbols]

1 light source, 2 condensed light beam, 4, 4a, 4b sensor, 5
Light valve drive circuit, 6 columnar optical element, 7 lens means, 9, 9a rotary filter unit, 12 light valve, 13 prism, 14 projection lens, 16
Observer, 41 light emitting element, 42 light receiving element, 43 slit, 44 package, 45 light emitting section, 46 light receiving section, 47 light transmitting space, 91a color filter, 92 motor.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03B 21/14 G03B 33/12 33/12 H01L 31/12 G H01L 31/12 H04N 9/31 C H04N 9 / 31 G02F 1/1335 530 F term (reference) 2H088 EA13 EA16 HA06 HA12 HA24 MA16 MA20 2H091 FA02Z FA26X FA48Z FD26 GA11 LA11 LA15 2H093 NA65 NC43 NC44 NC56 NC59 ND17 ND42 NE06 5C060 AA07 BA04 GB02 GB01 GB05 HC17 HD02 5F089 BA05 BB05 CA21

Claims (5)

[Claims] 1. A light source, a rotating filter unit including a plurality of color filters for selectively coloring outgoing light from the light source in a time-division manner, and illuminated by the outgoing light colored by the color filter A light valve, a sensor for sensing the rotation of the rotary filter unit based on time-division selective coloring of the color filter, and driving of the light valve for image formation based on a signal provided from the sensor. A projection display device comprising: a light valve driving circuit; and projection lens means for enlarging and projecting an image formed in an image display area of the light valve. 2. The projection display device according to claim 1, wherein the sensor includes a light-emitting element and a light-receiving element which are arranged to face each other at a predetermined interval, and wherein the color filter is provided within the interval. A projection type display device, wherein a peripheral portion of the projection type display device is rotatably inserted. 3. The projection display device according to claim 2, wherein a slit is arranged at least on a light receiving surface side of the light receiving element. 4. The projection display according to claim 3, wherein the width w of the slit satisfies the condition of the formula (1) when the light receiving area of the light receiving element is φ. A projection display device characterized by the above-mentioned. φ / w> 3 (1) 5. The projection display device according to claim 1, wherein the sensor includes a light emitting element and a light receiving element which are arranged adjacent to each other, and the sensor includes a light emitting element and a light receiving element which are opposed to the light emitting element and the light receiving element. A projection display device, wherein a peripheral portion is rotatably arranged.