Source: https://patents.google.com/patent/US20050018150A1/en
Timestamp: 2020-08-14 09:26:36
Document Index: 657587888

Matched Legal Cases: ['art 230', 'art 230', 'art 230', 'art 230', 'art 230', 'art 230', 'art 230']

US20050018150A1 - Projector - Google Patents
US20050018150A1
US20050018150A1 US10/872,385 US87238504A US2005018150A1 US 20050018150 A1 US20050018150 A1 US 20050018150A1 US 87238504 A US87238504 A US 87238504A US 2005018150 A1 US2005018150 A1 US 2005018150A1
US10/872,385
US6981773B2 (en
2003-07-16 Priority to JP2003-198136 priority Critical
2003-07-16 Priority to JP2003198136A priority patent/JP3997958B2/en
2004-06-22 Application filed by Seiko Epson Corp filed Critical Seiko Epson Corp
2004-10-04 Assigned to SEIKO EPSON CORPORATION reassignment SEIKO EPSON CORPORATION ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: YONEKUBO, MASATOSHI, KAMIJIMA, SHUNJI
2005-01-27 Publication of US20050018150A1 publication Critical patent/US20050018150A1/en
2006-01-03 Publication of US6981773B2 publication Critical patent/US6981773B2/en
A projector includes a super-high pressure mercury lamp a spatial light-modulator that modulates a light from the super-high mercury lamp based on an image signal, a projection lens that projects the light modulated, and an optical filter that is used to insert a prism group in the optical path and to remove the prism group that is inserted in the optical path, and a position fixing part that makes a relative-angle between each spatial light-modulator and the prism group constant.
FIG. 1 is a schematic of a projector according to a first embodiment of the present invention. A super-high pressure mercury lamp 101 generates a light that includes a red light, a green light, and a blue light (hereinafter, “R-light”, “G-light”, and “B-light”, respectively).
An integrator 104 uniforms an illuminance distribution of the light. A polarization converter 105 changes the light with the uniform illuminance-distribution into a polarized light such as an s-polarized light. The s-polarized light enters into a red-light transmitting dichroic mirror 106R. The red-light transmitting dichroic mirror 106R transmits the R-light, but reflects the G-light and the B-light. The dichroic mirrors separate the light into the R-light, the G-light, and the B-light in order.
The first-color spatial light modulator 110R includes a λ/2 wave plate 123R, a glass plate 124R, a first polarizing plate 121R, a liquid crystal panel 120R, and a second polarizing plate 122R. The λ/2 wave plate 123R and the first polarizing plate 121R sandwich a glass plate 124R, so that the heat does not distort the λ/2 wave plate 123R and the first polarizing plate 121R. The glass plate 124R is transparent and does not affect the polarization. The second polarizing plate 122R may be attached to the emergent surface of the liquid crystal panel 120R or the incident surface of a cross dichroic prism 112.
The first-color spatial light modulator110R modulates the R-light as follows. The λ/2 wave plate 123R changes the s-polarized R light into a p-polarized R light. After passing though the glass plate 124R and the first polarizing plate 121R, the p-polarized R-light enters into the liquid crystal panel 120R. The liquid crystal panel 120R modulates the p-polarized R-light based on the image signal corresponding to red and changes the p-polarized R-light into an s-polarized R-light. Then the second polarizing plate 122R outputs the s-polarized R-light to the cross dichroic prism 112.
The B-light is s-polarized when the B-light enters into the third-color spatial light modulator 110B. The λ/2 wave plate 123B changes the s-polarized B-light into a p-polarized B-light. After passing though the glass plate 124B and the first polarizing plate 121B, the p-polarized B-light enters into the liquid crystal panel 120B. The liquid crystal panel 120B modulates the s-polarized B-light based on an image signal corresponding to blue and changes the s-polarized G-light into a p-polarized G-light. Then the second polarizing plate 122B outputs the s-polarized B-light to the cross dichroic prism 112. Thus, the red-light transmitting dichroic mirror106R and the blue-transmitting dichroic mirror 106G separate the light from the super-high pressure mercury lamp 101 into the R-light, the G-light, and the B-light.
The dichroic prism 112 includes two dichroic layers 112 a, 112 b that are crossed each other. The dichroic layer 112 a reflects the B-light and transmits the R-light and the G-light, while the dichroic layer 112 b reflects the R-light and transmits the B-light and the G-light. In this manner, the dichroic prism 112 synthesizes the R-light, the G-light, and the B-light that are modulated by the first-color spatial light modulator, the second-color spatial light modulator, and the third-color spatial light modulator, respectively. The synthesized light is incident on an optical filter 130, and the light transmitted is incident on a projection lens 114. Then the projection lens 114 projects the light combined by the dichroic prism 112 onto a screen 166 to display a full-color image.
The optical filter 130, which can be inserted in the optical path and be removed from the optical path, is located on a side where each spatial light-modulators 110R, 110G, 110B outputs the light. The optical filter 130 includes a prism group 210, which is a refracting optical element, and a parallel plate 250, which is another optical element and optically transparent. When the projector 100 projects the image like a film (hereinafter, “picture image”), the prism group 210 is inserted in the optical path while the parallel plate 250 is removed from the optical path.
Referring back to FIG. 2, a motor (not shown) moves the optical filter to the direction that is substantially orthogonal to the optical axis AX using a lever 240, and inserts the prism group 210 or the parallel plate 250 in the optical path. Four guides 220 a, 220 b, 220 c, and 220 d control the moving direction of the optical filter to the direction of an arrow A. To insert the prism group 210 in the optical path, the optical filter 130 is moved till an end of the optical filter 130 makes a contact with a position fixing part 230 a. When the end of the optical filter 130 makes a contact with the position fixing part 230 a, the relative angle between the prism group 210 and the pixel parts of the spatial light-modulators 110R, 110G, and 110B is constant. The position fixing part 230 a is made of elastic material like a spring and another position fixing part 230 b is the same.
When the projector 100 projects the text image, such as a character, in the presentation, the parallel plate 250 is inserted in the optical path. To insert the parallel plate 250 in the optical path, the optical filter 130 is moved farther to the direction of the arrow A while bowing down the position fixing part 230 a, and the position fixing part 230 b stops the optical filter 130 by making a contact with another end of the optical filter 130. When the position fixing part 230 b makes a contact with another end of the optical filter 130, the parallel plate 250 is inserted in the optical path while the prism group 210 is removed from the optical path.
FIG. 4 and FIG. 5 are schematics for illustrating components on the optical path from each spatial light-modulator 110R, 110G, and 110B to the screen 116. The components on the optical path from the super-high pressure mercury lamp 101 to each spatial light-modulator 110R, 110G, and 110 B are same as those of the first embodiment.
Therefore the same components are not shown in FIG. 4 and FIG. 5, the same reference symbols are applied to the same components, and the explanations of the same components are omitted. A red-light optical filter 401, which can be inserted in the optical path and removed form the optical path, is located on the optical path and between the red-light spatial light-modulator 110R and the cross dichroic prism 112. The red-light optical filter 401 R includes the prism group. A motor M is configured to have functions for inserting the red-light optical filter 401R in the optical path and for removing the red-light optical filter 401R from the optical path. The red-light optical filter 401R, shown in FIG. 4, is on the optical path.
Similarly with the other embodiments, the optical filter 601, which is circular, includes a prism group 610 and a parallel plate 650. The optical filter 601 also includes notches 602 a, 602 b, which is a kind of position fixing part, on the opposite edges. The projection lens 114 includes a protrusion (not shown) that is made of elastic material like a spring. When the notch 602 a is engaged with the protrusion, the pixel of the prism group 610 makes a certain angle with each spatial light-modulator 110R, 110G, and 110B.
FIG. 7 is a cross section of the optical filter 601. The prism group 610 is composed of micro prism elements that are arranged periodically. The micro prism element includes a refracting surface, which is a gradient, and a flat surface. The refractive index and the thickness of the parallel plate 650 are configured to be optically equal to those of the prism group 610. The optical filter 601 includes a reflection reducing film on a incident surface 601 a where the projection lens 114 outputs the light, so that a light L that the projection lens 114 outputs is not refracted on the incident surface 601 a and does not go back to the projection lens 114. The light that goes back is called a stray light and causes the flare and the ghost image. The reflection reducing film lessens the stray light, therefore, the projection image has the higher image quality. The light L that each spatial light-modulator 110R, 110G, and 110B modulates projects the image upward and makes a certain angle θ with an optical axis AX of the projection lens 114.
How the projector according to the present embodiment projects the picture image is explained with reference to FIG. 6A. When the projector projects the picture image, the optical filter 601 is rotated to insert the prism group 610 in the optical path of the light that the projection lens 114 outputs. When the prism group 610 is inserted in the optical path, the notch 602 a is engaged with the protrusion, and the pixel of the prism group 610 makes a certain angle with each spatial light-modulator 110R, 110G, and 110B.
How the projector according to the present embodiment projects the text image is explained with reference to FIG. 6B. When the projector projects the test image, the parallel plate 650 is inserted in the optical path of the light that the projection lens 114 outputs while the prism group 610 is removed from the optical path. To insert the parallel plate 650 in the optical path, the optical filter 601 is rotated to the direction of an arrow A till the notch 602 b is engaged with the protrusion. The light passes through the parallel plate650 and projects the sharp text image. Moreover, the optical length of the prism group 610 is substantially equal to that of the parallel plate 650, so that the projector projects the text image in focus even when the parallel plate 650 is inserted in the optical path. The optical filter is arranged close to the opening of the projection lens 114 and protects the lens of the projection lens 114.
The spatial light-modulator 830 includes, for example, a plurality of rectangular diffraction elements that are lined up. The rectangular diffraction elements work independently based on the electronic signal. The amount of the motion of the diffraction element controls the amount of the diffraction light. The laser-light source 802 outputs the light to a component of the beam-shaping optical system (not shown). The component forms the laser light in the form of a line (hereinafter, “linear laser light”), and the long side of the leaner laser light is formed to correspond to the long side of the spatial light modulator 803.
a spatial light-modulator that modulates the light based on an image signal and outputs a modulated light;
a projection lens that projects the modulated light to display an image on a screen; and
an optical element inserting unit that inserts a first optical element in an optical path, wherein
the optical element inserting unit includes a position fixing unit that keeps an angle between the spatial light-modulator and the first optical element constant.
the optical element inserting unit further includes a second optical element, and selectively inserts the first optical element or the second optical element in the optical path, and
a first optical length when the first optical element is inserted in the optical path is substantially equal to a second optical length when the second optical element is inserted in the optical path.
the first optical element is either of a refracting optical element and a diffracting optical element, and
the second optical element is a transparent plate.
4. The projector according to claim 1, wherein the optical element inserting unit is arranged in the optical path between the spatial light-modulator and the projection lens.
5. The projector according to claim 1, wherein the optical element inserting unit is arranged between the projection lens and the screen.
US10/872,385 2003-07-16 2004-06-22 Projector Expired - Fee Related US6981773B2 (en)
JP2003-198136 2003-07-16
US20050018150A1 true US20050018150A1 (en) 2005-01-27
US6981773B2 US6981773B2 (en) 2006-01-03
US10/872,385 Expired - Fee Related US6981773B2 (en) 2003-07-16 2004-06-22 Projector
US20060050250A1 (en) * 2004-09-07 2006-03-09 Coretronic Corporation Correcting apparatus for projection system
US20100171865A1 (en) * 2009-01-07 2010-07-08 Sony Corporation Solid-state image-taking apparatus, manufacturing method thereof, and camera
US4482224A (en) * 1982-10-04 1984-11-13 Victor Hasselblad Aktie Bolag Compensation device at projectors with exchangeable and vertically movable lenses
JPH07225363A (en) * 1993-12-17 1995-08-22 Matsushita Electric Ind Co Ltd Liquid crystal projection device and liquid crystal display device
JP3518390B2 (en) 1999-02-22 2004-04-12 ノーリツ鋼機株式会社 Photo printing equipment
JP2001194729A (en) 2000-01-12 2001-07-19 Noritsu Koki Co Ltd Printing device, printing method and photographic processing device
2003-07-16 JP JP2003198136A patent/JP3997958B2/en not_active Expired - Fee Related
2004-06-22 US US10/872,385 patent/US6981773B2/en not_active Expired - Fee Related
2004-06-25 EP EP04253830A patent/EP1501292A3/en not_active Withdrawn
2004-07-12 CN CNB2004100690179A patent/CN100405211C/en not_active IP Right Cessation
2004-07-15 KR KR20040054991A patent/KR100645644B1/en not_active IP Right Cessation
US7347569B2 (en) * 2004-09-07 2008-03-25 Coretronic Corp. Correcting apparatus for projection system
US8619176B2 (en) * 2009-01-07 2013-12-31 Sony Corporation Solid state imaging device having lens and material with refractive index greater than 1 between the lens and imaging chip
US9313385B2 (en) 2009-01-07 2016-04-12 Sony Corporation Solid-state image-taking apparatus to focus incoming light into an image, manufacturing method thereof, and camera
EP1501292A2 (en) 2005-01-26
CN1577055A (en) 2005-02-09
KR100645644B1 (en) 2006-11-15
US6981773B2 (en) 2006-01-03
CN100405211C (en) 2008-07-23
JP3997958B2 (en) 2007-10-24
KR20050009194A (en) 2005-01-24
EP1501292A3 (en) 2005-04-27
JP2005037504A (en) 2005-02-10
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:KAMIJIMA, SHUNJI;YONEKUBO, MASATOSHI;REEL/FRAME:015216/0676;SIGNING DATES FROM 20040906 TO 20040910