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JPH10161237A Expired / Lapsed JP ⏱️ 0.0 years remaining

Lighting device and projector

Assignee: Canon Inc
•
Filing: 1997-10-02
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Granted: —
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Expires: 2017-10-02
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Abstract

Abstract Translated from Japanese (57)【要約】 【課題】 液晶表示装置の各点を照明する光束の主光線 が表示面に対して略垂直に入射するようにし、且つ液晶 表示装置の画像表示面の中心から隅まで照明光線の角度 がバラツキを無くして、明るく、色ムラが少なく簡易な 構成の照明装置及びプロジェクターを得ること。 【解決手段】 光源からの白色光を光学系によってテレ セントリックな状態として出射させて、被照明面へ導光 する照明装置であって、該光学系は、正の屈折力を有す る第1レンズと負の屈折力を有する第2レンズを備え、 該第1レンズと第2レンズとは互いに材質のアッベ数が 異なること。 (57) [Summary] [PROBLEMS] To make a principal ray of a light beam illuminating each point of a liquid crystal display device substantially perpendicular to a display surface, and to illuminate from the center to the corner of the image display surface of the liquid crystal display device. An illumination device and a projector having a simple configuration in which the angle of a light beam does not vary, is bright, has less color unevenness, and is simple. An illuminating device that emits white light from a light source in a telecentric state by an optical system and guides the light to a surface to be illuminated, wherein the optical system includes a first lens having a positive refractive power and a negative lens. A second lens having a refractive power of The first lens and the second lens have different Abbe numbers from each other.

Inventors

  • 👤 Takeshi Wada
  • 👤 健 和田

Bibliographic Details

Application Number —
Jurisdiction JP
Data Source google_patents
Last Synchronized 2026-11-09 14:24
CPC Classifications
H; H04; H04N; H04N9/00; H04N9/12; H04N9/31; H04N9/3102; H04N9/3105; H04N9/3108

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