Mitsubishi Electric Corporation

Mitsubishi Denki Kabushiki Kaisha

Takeshi Utakoji

Yuzo Nakano

Takao Endo

Akihisa Miyata

Shinsuke Shikama

Akihiro Yamada

Hiroshi Kida

Shinji Okamori

Yasuharu Koyata

Kenji Samejima

Shinji Yagyu

Tomohiko Sawanaka

A light source device includes a plurality of light sources with different polarizations. A combined wavelength band of the light of a first polarization and second polarization is a first wavelength band. A combined wavelength band of a third polarization and fourth polarization is a second wavelength band. A plurality of selective transmission elements transmits one or more combined light of one or more polarizations and reflects one or more light of one or more polarizations. Thus, the light of the first polarization, the light of the second polarization and the light of the third polarization passing through a third selective transmission element, and the light of the fourth polarization reflected by the third selective transmission element proceed in the same direction.

Light source device and projection-type display apparatus

Not only abnormality of a light output to an exterior but also overturning, vibration, disassembly, deformation, or breakage of a display apparatus including a case and a screen are reliably and promptly detected. A projection display apparatus includes a light source () for generating illumination light, which is provided in a case () having a light-shielding function, a movable aperture () for adjusting the amount of illumination light from the light source (), a light valve () for adjusting the amount of light based on an image signal to generate image light for forming an image from the illumination light, a projection optical system () for enlarging the image light from the light valve (), and a transmission-type screen () for displaying the image, which is provided to a window of the case (). The projection display apparatus further includes first to ninth detectors (to) for detecting the abnormality of the light output of the light source () to the exterior and the abnormality of the case () or the transmission-type screen (), a warning and alarm unit () for notifying the abnormality by sound or light, and a control unit () for controlling an internal operation when the abnormality is detected.

Projection display apparatus and method

A transparent screen and a projection display unit capable of reducing the speckle with maintaining the brightness of the image light. A wavefront-dividing phase-modulating componentwhich divides the wavefront of the image light emitted from a Fresnel lens screenand modulates the phases of the wavefronts divided, is disposed before an optical diffusing component. Alternatively, a spatial frequency modulating component, which modulates the spatial frequency of the image light diffused by the optical diffusing component, is disposed on the light-output side (observer side) of the optical diffusing component

Transparent screen and projection display unit

An illumination apparatus and a projection type display apparatus of lower cost are provided, in which extra-axial aberrations, especially distortion and lateral aberration, are favorably corrected, and the dimensional margin of illumination is suppressed to enhance the utilization factor of light. The illumination apparatus includes a first group of lenses which includes a meniscus lens having a positive refracting power, a second group of lenses which includes first lens means having a negative refracting power and second lens means having a positive refracting power, and lens means whose surface immediately before a surface to-be-illuminated is a plane surface, whereby an illuminating light beam is caused to exit in a telecentric state.

Illumination apparatus and projection type display apparatus

Growing community of inventors

Tokyo, Japan

Takeshi Utakoji