Mitsubishi Denki Kabushiki Kaisha

Mitsubishi Electric Corporation

Hitachi, Ltd.

Yoshiteru Suzuki

Hiroaki Sugiura

Shinsuke Shikama

Jun Someya

Kohei Teramoto

Akira Okumura

Akihiko Iwata

Hiroshi Ito

Shuichi Kagawa

Kuniko Kojima

Kouji Minami

Ikuro Suga

Isao Nakagawa

Shigeki Harada

Takayoshi Nagai

Masahiro Naito

Koji Minami

Akihiro Nagase

Masaharu Yao

Sadao Kubota

Toshimitsu Ozawa

Toru Suzaki

Tatsuo Shibata

A projection display uses a light modulating device to modulate, in accordance with image data, light radiated from a light source, project the modulated light onto a screen, and display an image. The projection display separates a unit of time configuring the image data into an effective light time when the light modulating device can express the light as an image on the screen and an ineffective light time when the light modulating device cannot express the light as an image on the screen. The projection display increases the power supplied to the light source during the effective light time over the power supplied to the light source during the ineffective light time.

Projection display

The object of the present invention is to provide an image display apparatus, an image processing apparatus, and an image display method that are able to display images without motion blur without increasing the transmitted amount of image signal. An image display apparatus of the invention comprises an image reception unit that receives an image signal; a gray-level correction unit that corrects image signals each corresponding to sub-frames consisting of a plurality of pixel groups split from the received mage signal, using respective grayscale characteristics different from sub-frame to sub-frame; and an image display unit that displays the frame image by successively displaying the sub-frame images each having been gray-level-corrected.

Image display apparatus, image processing apparatus, and image display method

There is disclosed a display device using a color wheel having a color filter Cw, in addition to normal color filters corresponding to the three primary colors. The filter Cw has almost flat spectral transmission characteristics. Brightness information included in a color image signal is quantized with (n+m) bits. Information corresponding to the lower-order n bits is displayed by light transmitted through the filter Cw. Information corresponding to the upper-order n bits is displayed by light transmitted through the normal color filters. Only brightness information to which the human eye is visually sensitive is reproduced by the filter Cw having a lower transmissivity. This can eliminate a lack of the number of gray levels due to a constraint on the minimum switching speed of a light valve. Furthermore, the brightness little deteriorates.

Display device for displaying digital input image data using different filter segments for the lower and higher order bits

A video signal sampling apparatus for sampling an input analog video signal by use of a sampling clock, and producing a digital signal which represents a level of a resultant video signal sample as a digital video signal is disclosed. The video signal sampling apparatus includes N (N being an integer equal to or greater than 2) converters for sampling the input analog video signal by use of N sampling clocks having phases that are different from each other to produce N digital signals which represent levels of N resultant video signal samples respectively, and a selector for selecting one digital signal from the N digital signals produced by the N converters in order that an amplitude of the digital video signal output to the outside is maximized.

Method and apparatus for selective video signal sampling

A gamma correction circuit has a data group generator which stores first to n-th gamma correction tables, receives first to n-th gains, and adjusts a level of the input signal using the first to n-th gamma correction tables and the first to n-th gains, thereby producing a gamma-corrected data group including first to n-th gamma-corrected data. The circuit also has a gamma characteristic controller which loads the first to n-th gains into the data group generator, a signal level discriminator which outputs a discrimination signal based on the level of the input signal, the first to n-th gamma correction tables, and the first to n-th gains, and an output selector which selects from among the first to n-th gamma-corrected data on the basis of a value of the discrimination signal, thereby producing the gamma-corrected output signal.

Gamma correction circuit

In an image display which reproduces a color image by using lights color-separated into four or more colors through color filters, the objects of the invention are to effectively utilize the energy of light from a light source and to reduce the effect that a slight shift of the spectral transmittance characteristics of the color filters exerts on the spectral distributions of the lights after color separated. In an image display having a light source and four or more kinds of color filters and for color-separating light emitted from the light source into four or more colors through the four or more kinds of color filters and reproducing a color image by using the color-separated lights, the spectral transmittance characteristics of the color filters are set so that the cutoff wavelengths of the four or more kinds of color filters exist in a wavelength region in which the spectral distributions obtained by multiplying the spectral emissivity characteristic of the light emitted from the light source by the color matching functions are smaller than the values obtained by multiplying the average values of the spectral distributions in the wavelength region from 380 to 780 nm by an integer.

Image display performing color reproduction using color filters

In an on screen display apparatus and an on-screen display method, the number of scanning lines of an input signal is detected. In accordance with the result of the detection, a vertical dot number of a character to be displayed is determined and font data is read from a memory device after adjusting a dot number of a blank portion of the font data. Hence, even if the number of the scanning lines changes, the number and positions of characters displayed in one screen remain constant.

On-screen display apparatus and on-screen display method

A motion detecting circuit is used for a motion-adapted scanning line interpolating circuit in a television system. The motion detecting circuit comprises an inter-frame correlation detecting circuit for detecting and outputting the value of correlation of video signals between adjacent frames, an inter-field correlation detecting circuit for detecting and outputting the value of correlation of signals of corresponding pixels between adjacent fields and an adjusting circuit for adjusting the output of the inter-frame correlation detecting circuit in accordance with the correlation value outputted from the inter-field correlation detecting circuit. An interlace/non-interlace signal converting circuit is also provided with the motion detecting circuit.

Motion detecting circuit for video signal processing using correlation

Growing community of inventors

Tokyo, Japan

Yoshiteru Suzuki