Canon Kabushiki Kaisha

Toshiyuki Kanda

Hiroshi Takabayashi

Yoshihiro Onitsuka

Hideo Mori

Makiko Mori

Tatsuro Yamazaki

Kohei Inamura

Takashi Yamamoto

Izumi Kanai

Hisao Tajima

Yukio Hiraki

Masaru Tada

Katsumi Kurematsu

Eisaku Tatsumi

Kazuhiro Matsubayashi

Masanori Takahashi

An image processing apparatus for controlling brightness of an image to be output to a display unit includes a separation unit which separates an input image into images in a plurality of areas, and an entropy calculation unit which calculates, for the image in each area, entropy information on at least one of distribution of luminosity, character quantity, and motion quantity. In addition, a brightness control unit controls brightness for the image in each area so that a first reduction rate of brightness in an area of which entropy is relatively small is greater than a second reduction rate of brightness in an area of which entropy is relatively large.

Image processing apparatus and image processing method

The present invention relates to an image display apparatus for forming an image with a plurality of luminescent spots to be precisely aligned in a matrix. For example, a spacer disposed between an electron source and a face plate causes luminescent spots on the face plate spaced unevenly. The luminescent spots spaced unevenly will produce a visual unevenness in luminance which deteriorates the quality of produced image. By modifying the quantity of light of luminescent spots spaced unevenly, the visual unevenness in luminance is compensated.

Image display apparatus for forming an image with a plurality of luminescent points

A color display apparatus, such as a color liquid crystal display apparatus, is composed of a multiplicity of sub-pixels each designed for displaying one of a plurality (k) of mutually different mono-colors and arranged in rows and columns so as to form pixels each with a plurality of mutually adjacent sub-pixels. The sub-pixels and pixels are so arranged that a number n given by dividing a total number of sub-pixels arranged in a row or column with a total number of pixels arranged in the row or column is set to satisfy: 1<n<k, wherein k denotes the plurality of the mono-colors displayed by the sub-pixels. As a result, the pixel pitch can be reduced to provide an increased display density and an improved display quality.

Color display apparatus

A backlight device suitable for illuminating a transmission-type display device, such as a liquid crystal device, is constituted by a reflection member for reflecting light, a transmission member disposed opposite to the reflection member so as to form a space from the reflection member, and a light source disposed to emit light into the space. Light issued from the light source into the space is reflected by the reflection member and transmitted through the transmission member. The transmission member is preferably provided with a reflection layer having apertures having an aperture ratio which increases with an increase in distance from the light source toward a center of the space in a linear function, a hyperbolic function or a function intermediate therebetween of the distance from the light source. Between the transmission member and the display device, a prism sheet and/or a diffusion sheet may be disposed so as to improve the frontal illumination performance.

Backlight device for display apparatus

An illumination device for a liquid crystal display apparatus to be disposed on a back side of a liquid crystal display panel is constituted by a plurality of illumination circuits, and plural hot cathode tubes including at least one hot cathode tube associated with each illumination circuit. Each illumination circuit includes a life detection circuit for detecting an end of life of a hot cathode tube, and a turn-off circuit for turning off the hot cathode tube depending on an output of the life detection circuit. Each illumination circuit controls said at least one hot cathode tube associated therewith independently from the other hot cathode tubes. As a result, even when a hot cathode tube approaches its end of life, the illumination device can be partially turned off to allow an operator to continue the operation on the liquid crystal display apparatus.

Illumination device for liquid crystal display apparatus

An illumination device includes a plurality of linear light sources disposed with a prescribed spacing therebetween, a light guide means disposed between or among the linear light sources, and a reflection means disposed behind the light guide means so that light issued from the linear light sources is transmitted through the light guide means and reflected by the reflection means to be emitted in a direction forward from the light guide means. Further, a luminance distribution-adjusting means for reflecting light transmitted through the light guide means is disposed along the light guide means in a disribuption density which varies continuously at a changing rate free from discontinuity so as to adjust the luminance distribution of the light emitted in the direction forward from the light guide means. The illumination device may be suitably used as a backlight behind a liquid crystal panel to provide a liquid crystal display apparatus having improved display qualities.

Illumination device and liquid crystal display apparatus including same

An illumination device includes: a linear light source; first reflection means disposed opposite to and with a spacing from the linear light source; a light guide means disposed between the linear light source and the first reflection means; and a second reflection means disposed behind the light guide means so that light issued from the linear light source is transmitted through the light guide means and reflected by the first and second reflection means to be emitted in a direction forward from the light guide means. Further, a luminance distribution-adjusting means for reflecting light transmitted through the light guide means is disposed along the light guide means in a distribution density which varies at a changing rate free from discontinuity so as to adjust the luminance distribution of the light emitted in the direction forward from the light guide means. The illumination device may suitably be used as a backlight unit for a liquid crystal panel to provide a liquid crystal display apparatus having improved display qualities.

Illumination device with luminance distribution adjusting reflection

A surface lighting device receiving incident rays through two opposing faces of a light guide from light source to emit the incident rays from a face different from the two faces. The light guide is divided into plural divisions which are jointed together.

Growing community of inventors

Chigasaki, Japan

Toshiyuki Kanda