Pioneer Electronic Corporation

Toru Yokoo

Hideki Yamamoto

Akihiko Seki

Takashi Nagashima

Motoharu Hirai

Katuzi Suzuki, Deceased

Takashi Kobane

Yoshikazu Kawakami

A rear projection television set in which a lenticular sheet is superposed to a Fresnel lens to form a light transmissive screen, at least one projection cathode ray tube projects an image onto the Fresnel lens so that the image through the lenticular is viewed by a viewer. A projector lens is mounted to the projection cathode ray tube and has an exit pupil so as to project the image from the projection tube onto the Fresnel lens. The image through the lenticular sheet is viewed at a distance from the lenticular lens, wherein there is a relation a.times.b&lt;5.5 where a is distance between the exit pupil of the projector lens 2 and the Fresnel lens 1, and b is a condensing distance for a maximum radius equal to the vertical dimension of the screen.

Rear projection television set with lenticular sheet and fresnel lens

A rear-projection television has a transmission type two-layer screen made up of a Fresnel lens and a lenticular lens stacked together. Between the two lenses is interposed a transparent protective sheet which protects the lenses from wear or score, which would otherwise result from rubbing due to vibrations during shipping. The use of a transparent protective sheet sandwiched between the two lenses permits a series of adjustments and a final inspection on the TV to be made with the product screen mounted in the cabinet. This eliminates the need to mount a jig screen identical with the product screen in place of the latter during the adjustments, reducing the overall amount of time spent in the manufacturing process.

Rear projection television

A lenticular lens is provided for use in a back projection type television receiver. The lenticular lens is provided with an exit face having formed thereon a lens portion and two reflecting portions. The lens portion refracts light from a lenticule before the light emerges therefrom. The reflecting portions are on both sides of said lens portion, and each has a reflecting face erected with respect to the screen surface. Part of the incident light is totally reflected by the reflecting portion toward the lens portion whereby the light emerges from the lens portion. Because of this arrangement, the pitch between adjacent lenticules or exit faces can be reduced without rendering the lenticular lens unduly thin.

Lenticular lens for use in back projection type television receiver

A rear projection screen comprises, in combination, a Fresnel lens having concentric annular ridges arranged at a radial pitch of P1, and a lenticular lens having parallel lenticulars arranged at a pitch P2. The pitch ratio P1/P2 between the pitches P1 and P2 is determined in the range of 0.1505 to 0.1545 or in the range of 0.176 to 0.181. The rear projection screen meeting such a condition suppresses effectively the moire effect of the concentric annular ridges of the Fresnel lens and the parallel lenticulars of the lenticular lens disposed adjacent to the Fresnel lens.

Rear projection screen

A rear-projection television has a transmission type two-layer screen made up of a Fresnel lens and a lenticular lens stacked together. Between the two lenses is interposed a transparent protective sheet which protects the lenses from wear or score, which would otherwise result from rubbing due to vibrations during shipping. The use of the transparent protective sheet sandwiched between the two lenses permits a series of adjustments and a final inspection on TV to be made with the product screen mounted in the cabinet. This eliminates the need to mount a jig screen identical with the product screen in place of the latter during the adjustments, reducing the overall amount of time spent in the manufacturing process.

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Tokyo, Japan

Toru Yokoo