Seiko Epson Corporation

Shuji Aruga

Tomio Sonehara

Shinji Morozumi

Akitaka Yajima

Junichi Nakamura

Hirosada Horiguchi

Hiroshi Kamakura

Takeshi Ono

A projection display for preventing reflected light beams produced during optical modulation or light compositing from reinjecting into the modulating liquid crystal panel, as well as to convert projected light or light impinged into a light compositing system into a linearly polarized light beam, thereby projecting high-contrast, high-intensity images with minimal reflection errors. This display will preferably include a light source, an optical modulation system for modulating the light beam emitted from the light source according to a video signal using a liquid crystal panel having a polarizing plate or filter on the output surface thereof, a first phase plate provided on the output side of the polarizing plate for converting the linearly polarized light beam that has passed through the optical modulation system into a circularly polarized light beam, a second phase plate provided on the output side of the first phase plate for converting the circularly polarized light beam that has passed through the first phase plate into a linearly polarized light beam, and an optical projector system for projecting on a screen in enlarged fashion the resultant linearly polarized light beam that has passed through the second phase plate. The first and second phase plates are preferably disposed such that reflected light produced at interfaces between air and the first or second phase plates, or a light compositor are polarized at right angles to the light transmission axis of the interposing polarizing plate, thereby blocking their passage back to the liquid crystal panel.

Projection display employing circular polarized light for reflection

A projection-type display device having a single light source which produces light. A first dichroic mirror group receives the light and separates it into colored light. A transmissive light valve system modulates the colored light and a second dichroic mirror group synthesizes the modulated colored light. A projection system projects the synthesized colored light onto a screen.

Projection-type display device

A projection-type display device having a single light source which produces light. A first dichroic mirror group receives the light and separates it into colored light. A transmissive light valve system modulates the colored light and a second dichroic mirror group synthesizaes the modulated colored light. A projection system projects the synthesized colored light onto a screen.

A projection-type display device having a single light source which produces light. A first dichroic mirror group receives the light and separates it into colored light. A transmissive light valve system modulates the colored light and a second dichoric mirror group synthesizes the modulated colored light. A projection system projects the synthesized colored light onto a screen.

A projection-type display device using twisted nematic liquid crystal light valves in which the photoelectric transfer characteristics of three light valves for selectively transmitting red, green and blue light to a synthesizing device are matched. The product of the birefrigence .DELTA.n and thickness d of the twisted nematic liquid crystal and thickness of cell is selected to fall within a predetermined optimal range of values depending upon the wavelength of light which travels therethrough. The thickness d or birefrigence .DELTA.n of the twisted nematic liquid crystal material of each light valve may be the same.

A projection-type display device for producing a faithful colored synthesized image based on equating the luminous intensity distributions and light patterns produced by three twisted nematic liquid crystal light valves for three primary color images. Each light valve includes a twisted nematic liquid crystal composition which is twisted to the right or left depending on the number of times that color light is reflected. Each light valve may include an active switching matrix arranged in mirror-like symmetry with light shield layers also arranged symmetrically.

Projection-type liquid crystal display device with even color

A projection-type color display device. The display device includes a light source which provides light and a color separation member which receives the light and which separates the received light into the different colors of red, blue and green light. A light valve device receives the red, blue and green light and modulates the light to produce images. A color synthesis cube prism synthesizes the three monochromatic lights modulated by the light valve. A projection lens system projects the synthesized image onto a screen for viewing.

Growing community of inventors

Suwa, Japan

Shuji Aruga