US5613748A — Rear projection type image display apparatus and …

Claim 1

Independent Claim 207 words

A rear projection type image display apparatus comprising at least one image generator source for displaying images, at least one projection lens for enlarging images displayed on the at least one image generation source and a transmission screen for displaying the enlarged images projected onto a rear portion of the transmission screen, the transmission screen of the image display apparatus having directional characteristics such that when a direction which permits viewing a central image on a picture plane of the transmission screen in a brightest state of the images projected onto the transmission screen is assumed to be a reference direction, the luminance of the picture plane center is not less than 50% of the luminance in the reference direction, in a horizontal direction of 50° relative to the reference direction; the luminance is not less than 10% of the luminance in the reference direction, in a horizontal direction of 65° relative to the reference direction; the luminance is not less than 50% of the luminance in the reference direction, in a vertical direction of 10° relative to the reference direction; and the luminance is not less than 10% of the luminance in the reference direction, in a vertical direction of 25° relative to the reference direction.

Claim 2

Dependent Claim 207 words

A rear projection type image display apparatus comprising at least one image generator source for displaying images, at least one projection lens for enlarging images displayed on the at least one image generation source and a transmission screen for displaying the enlarged images projected onto a rear portion of the transmission screen, the transmission screen of the image display apparatus having directional characteristics such that when a direction which permits viewing a central image on a picture plane of the transmission screen in a brightest state of the images projected onto the transmission screen is assumed to be a reference direction, the luminance of the picture plane center is not less than 50% of the luminance in the reference direction, in a horizontal direction of 50° relative to the reference direction; the luminance is not less than 10% of the luminance in the reference direction, in a horizontal direction of 65° relative to the reference direction; the luminance is not less than 50% of the luminance in the reference direction, in a vertical direction of 10° relative to the reference direction; and the luminance is not less than 10% of the luminance in the reference direction, in a vertical direction of 25° relative to the reference direction.

Claim 3

Dependent Claim 51 words

A rear projection type image display apparatus according to claim 1, wherein the transmission screen includes a Fresnel lens sheet arranged for receiving the images enlarged and projected by the projection lens and a lenticular lens sheet proximate to the Fresnel lens sheet for enabling display of the images for viewing.

Claim 4

Dependent Claim 107 words

A rear projection type image display apparatus according to claim 2, wherein the Fresnel lens sheet includes a light incidence surface for receiving the projected images from the projection lens, and a light exit surface of a Fresnel lens, the lenticular lens sheet including a light incidence surface proximate to the Fresnel lens of the Fresnel lens sheet and having a plurality of first vertical lenticular lenses, the lenticular lens sheet having a light exit surface having a plurality of second vertical lenticular lenses, the plurality of second vertical lenticular lenses being separated from one another by a convex portion having a light absorbing band formed thereon.

Claim 5

Dependent Claim 20 words

A rear projection type image display apparatus according to claim 3, wherein the light absorbing band is a glossy layer.

Claim 6

Dependent Claim 30 words

A rear projection type image display apparatus according to claim 3, wherein a width of the Fresnel lens sheet is substantially equal to a width of the lenticular lens sheet.

Claim 7

Dependent Claim 32 words

A rear projection type image display apparatus according to claim 3, wherein the lenticular lens sheet is formed of a light transmissive material without fine particles of a light diffusing material therein.

Claim 8

Dependent Claim 78 words

A rear projection type image display apparatus according to claim 3, wherein the transmission screen further includes a plurality of (a) horizontal lenticular lenses disposed one of at the light incidence surface of the Fresnel lens sheet and (b) at a light incidence surface of another lenticular lens sheet disposed proximate to the light exit surface of the Fresnel lens sheet, the another lenticular lens sheet being disposed between the Fresnel lens sheet and the lenticular lens sheet.

Claim 9

Dependent Claim 56 words

A rear projection type image display apparatus according to claim 7, wherein the horizontal lenticular lenses of one of the Fresnel lens sheet and the another lenticular lens sheet have an aspherical oval shape, and at least one of the first and second vertical lenticular lenses of the lenticular lens sheet have an aspherical non-oval shape.

Claim 10

Dependent Claim 34 words

A rear projection type image display apparatus according to claim 3, wherein the transmission screen further includes a translucent light absorbent sheet disposed proximate to the light exit surface of the lenticular lens sheet.

Claim 11

Dependent Claim 77 words

A rear projection type image display apparatus according to claim 2, further comprising a reflecting mirror disposed for reflecting images from the projection lens onto the rear portion of the transmission screen, the reflecting mirror including a photoreflective optical thin film formed on a base member, the photoreflective optical thin film being disposed on a surface of the base member closer to the projection lens and the transmission screen than an opposite surface of the base member.

Claim 12

Dependent Claim 209 words

A rear projection type image display apparatus comprising image generator means for generating and displaying images, projection lens means for projecting and enlarging images displayed on the image generation means and transmission screen means for transmitting and displaying the enlarged images projected onto a rear portion of the transmission screen means, the transmission screen means of the image display apparatus having directional characteristics such that when a direction which permits viewing a central image on a picture plane of the transmission screen means in a brightest state of the images projected onto the transmission screen means is assumed to be a reference direction, the luminance of the picture plane center is not less than 50% of the luminance in the reference direction, in a horizontal direction of 50° relative to the reference direction; the luminance is not less than 10% of the luminance in the reference direction, in a horizontal direction of 65° relative to the reference direction; the luminance is not less than 50% of the luminance in the reference direction, in a vertical direction of 10° relative to the reference direction; and the luminance is not less than 10% of the luminance in the reference direction, in a vertical direction of 25° relative to the reference direction.

Claim 13

Dependent Claim 209 words

A rear projection type image display apparatus comprising image generator means for generating and displaying images, projection lens means for projecting and enlarging images displayed on the image generation means and transmission screen means for transmitting and displaying the enlarged images projected onto a rear portion of the transmission screen means, the transmission screen means of the image display apparatus having directional characteristics such that when a direction which permits viewing a central image on a picture plane of the transmission screen means in a brightest state of the images projected onto the transmission screen means is assumed to be a reference direction, the luminance of the picture plane center is not less than 50% of the luminance in the reference direction, in a horizontal direction of 50° relative to the reference direction; the luminance is not less than 10% of the luminance in the reference direction, in a horizontal direction of 65° relative to the reference direction; the luminance is not less than 50% of the luminance in the reference direction, in a vertical direction of 10° relative to the reference direction; and the luminance is not less than 10% of the luminance in the reference direction, in a vertical direction of 25° relative to the reference direction.

Claim 14

Dependent Claim 34 words

A rear projection type image display apparatus according to claim 11, wherein the display apparatus has high horizontal directivity and the transmission screen means includes a vertically long lenticular lens having an aspherical shape.

Claim 15

Dependent Claim 27 words

A rear projection type image display apparatus according to claim 12, wherein the vertically long lenticular lens has a mirror surface as a light exit surface thereof.

Claim 16

Dependent Claim 26 words

A rear projection type image display apparatus according to claim 12, wherein the transmission screen means has a glossy layer as a light exit surface thereof.

Claim 17

Dependent Claim 33 words

A rear projection type image display apparatus according to claim 11, wherein the display apparatus has high vertical directivity and the transmission screen includes a horizontal long lenticular lens having an aspherical shape.

Claim 18

Dependent Claim 27 words

A transmission screen for use in a rear projection type image display apparatus, the transmission screen having a glossy light absorbing layer without a diffusing medium therein.

Claim 19

Dependent Claim 27 words

A transmission screen for use in a rear projection type image display apparatus, the transmission screen having a glossy light absorbing layer without a diffusing medium therein.

Claim 20

Dependent Claim 31 words

A transmission screen according to claim 16, wherein the glossy light absorbing layer includes a plurality of vertical black stripe portions provided at a light exit surface of the transmission screen.

Claim 21

Dependent Claim 60 words

A transmission screen according to claim 16, wherein the rear projection type image display apparatus comprises at least one image generation source for displaying images, at least one projection lens for enlarging images displayed on the at least one generation source and the transmission screen enables display of the enlarged images projected onto a rear portion of the transmission screen.

Claim 22

Dependent Claim 52 words

A transmission screen according to claim 18, wherein the transmission screen includes a Fresnel lens sheet arranged for receiving the images enlarged and projected by the projection lens and a lenticular lens sheet without a diffusing medium disposed proximate to the Fresnel lens sheet for enabling display of the images for viewing.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	2000-03-24	2000-09-23	2001-03-25	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	2004-03-24	2004-09-23	2005-03-25	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	2008-03-24	2008-09-23	2009-03-25	$7700.00	Window Closed / Lapsed

Rear projection type image display apparatus and transmission type screen used therein

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