Hitachi, Ltd.

Hitachi Maxell, Limited

Other

Hitachi Video Engineering, Incorporated

Hiatchi, Ltd.

Hitachi, Ltd., and Hitachi Video and Information Systems, Inc.

Takesuke Maruyama

Masahiko Yatsu

Yasuo Otsuka

Tomohiro Miyoshi

Satoshi Ohuchi

Masaharu Deguchi

Taro Imahase

Futoshi Yamasaki

Takashi Kakuda

Yutaka Matsuda

Hironobu Satoh

Takanori Hisada

Yasuyuki Sugi

Nobuyuki Kaku

Atsushi Ishibashi

Shigehisa Hagura

Takeshi Hoshino

Kenji Sano

Kenji Fuse

Naohiro Ozawa

Makoto Fukatsu

Takashi Azumi

Seiichi Sekiguchi

Takuya Shiaki

Mikiharu Kuwata

Yoshio Ariki

Koichi Umezawa

Nobuhiko Konuma

Hidetomo Yoshimura

Shigeyuki Itoh

Kenji Ogiro

Kenji Matsumoto

Yutaka Takami

Iwao Aizawa

Takanori Nishiyama

Manabu Wakabayashi

Toshio Murakami

Hiroshi Tomita

Shuzo Matsumoto

Hiroto Takita

Naohiro Konuma

Kenji Kobayashi

Hiroki Yoshikawa

Tetsu Ohishi

Hiroshi Sakurai

Takeshi Igarashi

Masao Obara

Yoshihiro Todaka

Yoshihiko Noro

Ichiro Niitsu

Hideo Tanide

Mitsuharu Akatsu

Toshiharu Shimizu

Shunichi Taguchi

Goro Ohnishi

Atushi Takeyama

Ryoichi Hirota

Takashi Iwata

Yoshifumi Honma

Kei Yamashita

When the DVD provided with the DVD substratehaving thickness tof 0.6 mm is installed in the optical disc apparatus, the light beamhaving wavelength &#x3bb;=655 nm is used as luminous flux of numerical aperture NA=0.63 to be condensed on the information surfaceon the DVD substrate. When the CD provided with the CD substratehaving thickness tof 1.2 mm is installed in the optical disc apparatus, the light beamhaving wavelength &#x3bb;=790 nm is effectively used as luminous flux of approximate numerical aperture NA=0.45 to be condensed on the information surfaceon the DVD substrate. The wavefront aberration caused by a thickness difference between the DVD substrateand CD substrateis canceled out by the chromatic aberration caused by a wavelength difference between the light beamsand. Therefore, in spite of the difference in the transparent substrates, the light beams are suitably condensed respectively on the information surfaceand

Objective lens design method, lens, and optical system, optical head, and optical disc apparatus using the same

When the DVD provided with the DVD substratehaving thickness tof 0.6 mm is installed in the optical disc apparatus, the light beamhaving wavelength &#x3bb;=655 nm is used as luminous flux of numerical aperture NA=0.63 to be condensed on the information surfaceon the DVD substrateWhen the CD provided with the CD substratehaving thickness tof 1.2 mm is installed in the optical disc apparatus, the light beamhaving wavelength &#x3bb;=790 nm is effectively used as luminous flux of approximate numerical aperture NA=0.45 to be condensed on the information surfaceon the DVD substrateThe wavefront aberration caused by a thickness difference between the DVD substrateand CD substrateis canceled out by the chromatic aberration caused by a wavelength difference between the light beamsandTherefore, in spite of the difference in the transparent substrates, the light beams are suitably condensed respectively on the information surfaceand

The present invention discloses the structure of the array lens that at least any one of the diagonal size, vertical size and lateral size of lens cell is set to almost 1/(4.5 or more) for each corresponding size of the display elements, the structure that the diagonal size of lens cell is set to almost 0.18 inch or less, the structure that the total number of lens cells is set to almost 240 or more and the structure that the lens focal distance of lens cell is set to almost 30 mm or less.

Optical unit and image display apparatus

A liquid crystal projector comprises an illuminating optical system including a light source, a color separating optical system for separating illuminating light rays emitted by the illuminating optical system into light rays of three colors, a projection lens unit comprising a projection lens, a cross dichroic prism disposed near a light receiving end of the projection lens, and a plurality of liquid crystal panels arranged around the cross dichroic prism, and a light source power supply for supplying power to the light source. The projection lens unit, the color separating optical system, the illuminating optical system and the light source power supply are arranged in that order. The liquid crystal projector has an outside size in a horizontal plane of 263 mm by 318 mm or below. The liquid crystal panels have a display screen size of 0.9 in. A cooling fan for cooling the plurality of liquid crystal panels is disposed beside the projection lens.

Liquid crystal projector, and projection lens unit, optical unit and cooling system for the same

When the DVD provided with the DVD substrate having thickness t of 0.6 mm is installed in the optical disc apparatus, the light beam having wavelength &lgr; &equals;655 nm is used as luminous flux of numerical aperture NA&equals;0.63 to be condensed on the information surface on the DVD substrate . When the CD provided with the CD substrate having thickness t of 1.2 mm is installed in the optical disc apparatus, the light beam having wavelength &lgr; &equals;790 nm is effectively used as luminous flux of approximate numerical aperture NA&equals;0.45 to be condensed on the information surface on the DVD substrate . The wavefront aberration caused by a thickness difference between the DVD substrate and CD substrate is canceled out by the chromatic aberration caused by a wavelength difference between the light beams and . Therefore, in spite of the difference in the transparent substrates, the light beams are suitably condensed respectively on the information surface and

The present invention discloses the structure of the array lens that at least any one of the diagonal size, vertical size and lateral size of lens cell is set to almost 1/(4.5 or more) for each corresponding size of the display elements. The diagonal size of lens cell is set to almost 0.18 inch or less. The total number of lens cells is set to almost 240 or more. Finally, the lens focal distance of lens cell is set to almost 30 mm or less.

Array lens, lighting optical system, optical unit and imaging apparatus

An enlarging unit comprises a concave Fresnel lens warped convexly toward an image forming unit side, the image forming unit is held between a light transmissible support plate warped convexly toward the image forming unit side and the enlarging unit warped convexly toward the image forming unit side, and peripheries of the support plate and the enlarging unit are fixed or semi-fixed. Thereby, deformation caused when the incident side and emission side micro-lens arrays are molded and deformation due to environmental temperature and humidity change are corrected, and both components are always maintained in close contact.

Image forming unit, enlarging unit, optical parts, and image display apparatus having these components

Growing community of inventors

Yokohama, Japan

Takesuke Maruyama