Casio Computer Co., Ltd.

Yasuhiro Daiku

Tetsuo Muto

Tomoyuki Shirasaki

Jun Ogura

Tetsushi Yoshida

Manabu Takei

Masaharu Shioya

Hiroyasu Yamada

Masaru Higuchi

Tetsuya Kusuno

Minoru Fujiwara

A surface light source includes first and second light sources that emit lights, and an optical deflection element. The optical deflection element changes light emitted from the first light source into first illumination light having a maximum value of an exit light intensity present in a direction parallel to a normal line of the surface light source, a spread angle range, and high directivity in a direction of the normal line and allows the changed light to exit therefrom. The optical deflection element also changes light emitted from the second light source into second illumination light having a maximum value of an exit light intensity in an oblique direction inclined at an angle with respect to the normal line and a spread angle range wider than that of the first illumination light and allows the changed light to exit therefrom.

Surface light source capable of changing range of spread angle of exit light, and liquid crystal display apparatus using this surface light source

A liquid crystal display apparatus has a liquid crystal display device, a surface light source, and a view angle limiting device arranged between the surface light source and the liquid crystal display device. The view angle limiting device includes first and second transparent plates facing each other with a gap therebetween, a plurality of first &#xbd; retardation layers having a predetermined shape formed to be spaced apart from each other on one of the facing inner surfaces of the first and second transparent plates, a plurality of second &#xbd; retardation layers formed on the other inner surface at regions corresponding to the regions between the first &#xbd; retardation layers, and a polarizing film provided at the outer surface of one of the first and second transparent plates that faces the surface light source.

Liquid crystal display apparatus capable of limiting view angle

Disclosed is a pressure sensor comprising: a substrate; a pressure reception plate which is provided in a state of facing the substrate, the pressure reception plate comprising in a surface which faces the substrate, a low reflection region, and a high reflection region having a relatively higher reflection ratio compared to the low reflection region; a support portion to change a distance between the substrate and the pressure reception plate when a pressure is applied to the pressure reception plate, the support portion being provided in between the substrate and the pressure reception plate; and a plurality of light receiving elements which are respectively provided on the substrate in positions facing the low reflection region and in positions facing the high reflection region, of the pressure reception plate.

Pressure sensor and pressure measurement method of pressure sensor

A display apparatus includes a display panel that displays an image, and a viewing angle restricting element that selectively irradiates light with directivity in a restricting direction at a predetermined angle with respect to a direction of normal to the display panel, toward an observation side of the display panel.

Display apparatus capable of controlling range of visually recognizable observation angle

A display apparatus includes a liquid crystal display panel and an illuminator disposed at the back of the panel for emitting at least two illumination lights having directivities in different directions toward the panel. The illuminator includes a light guide plate made of transparent material whose one end surface serves as a light entrance end surface, whose one plate surface serves as a light exit surface, and whose other plate surface serves as a light direction changing surface for changing the advancing direction of light entering from the light entrance end surface. The light direction changing surface has a plurality of circular-arcing slanted surfaces shaped into semicircles formed on concentric circles centered at the center of the longer dimension of the light entrance end surface. Light emitting elements are disposed on the light entrance end surface at two positions on left and right sides of the center equidistantly apart therefrom.

Illuminator for emitting at least two lights having directivity and display apparatus using same

A surface light source includes a light source which selectively irradiates two polarized light beams in polarized states different from each other, a light guide plate which includes a transparent plate having two plate surfaces facing each other and end faces surrounding the plate surfaces, and irradiates the two polarized light beams form an irradiation surface, and an optical element which irradiates irradiated light from the irradiation surface of the light guide plate toward a direction substantially normal to the light guide plate upon changing the propagation direction of the irradiated light. A liquid crystal display apparatus includes this surface light source, a polarization control element which is placed on the observation side of the surface light source and rotates the polarization plane of linearly polarized light transmitted through one of partitioned first and second areas through a predetermined angle, and a liquid crystal display device placed on the observation side.

Surface light source which selectively irradiates two linearly polarized light beams in polarized states different from each other and liquid crystal display apparatus using the same

A surface light source includes a light guide unit which allows two linear polarized lights having polarized planes perpendicular to each other to alternately exit from an exit surface in a direction substantially parallel with a normal line of the exit surface. A retardation element is arranged to face the exit surface. The retardation element has &#x3bb;/2 retardation portions which give a phase difference of a &#xbd; wavelength between ordinary light and abnormal light, and a plurality of non-retardation portions having substantially no phase difference alternately formed in a direction along the exit surface. A lens array is provided to face the light guide unit. The lens array allows light which has been transmitted through a &#x3bb;/2 retardation portion to exit in a first inclined exiting direction, and allows light which has been transmitted through a non-retardation portion to exit in a second inclined exiting direction.

Surface light source and liquid crystal display apparatus

A liquid crystal display apparatus comprises first and second light emitting sections for emitting light with respective spreading angles that are different from each other and a liquid crystal display device arranged at the viewing side of the apparatus. The first light emitting section includes a first light guide plate for receiving light from a light incident end surface and diffusing it within a first angular range of spreading angle centered at the normal direction of a light emitting surface before emitting it from the light emitting surface and first light emitting elements. The second light emitting section includes a second light guide plate for receiving light from a light incident end surface and emitting it in directions within a second angular range of spreading angle smaller than the first angular range while transmitting light emitted from the first light guide plate and second light emitting elements.

Surface light source capable of varying angular range for diffusing emitted light and liquid crystal display apparatus capable of displaying selectively with wide view angle and narrow view angle by using same

A display device includes an image display unit having one surface and the other surface on which first and second images are respectively displayed. A first optical system leads a first image light displayed on the one surface of the image display unit. A second optical system leads a second image light displayed on the other surface of the image display unit. An image combining element combines the first and second image lights lead by the first optical system and the second optical system to form one image.

Stereoscopic image display device comprising transmissive liquid crystal display element

A surface light source includes a prism sheet placed on one side of a liquid crystal display panel, and having elongated prism portions formed to form a patterned indented entrance surface having an angular cross-section, and an exit surface. A reflecting plate is placed to face the prism sheet through a space. First and second light source units are disposed on two end sides. A control unit sequentially writes left-eye image data and right-eye image data on respective pixels of the display panel, causes the light source unit on the right side when viewed from an observation side of the surface light source to emit light in synchronism with the writing of the left-eye image data, and causes the light source unit on the left side to emit light in synchronism with the writing of the right-eye image data.

Surface light source and liquid crystal display device using the same

A scanning head includes a surface emitting part array panel which has an array of surface emitting parts to emit light A plurality of light guide parts are respectively opposite to the surface emitting parts. Each of light guide parts has an entrance plane to receive the light from the surface emitting part, a reflection plane to reflect the light from the entrance plane, and an exit plane to emit the light from the reflection plane.

Scanning head and printer

The invention has light source unit disposed at opposite side to observer side of liquid crystal display device for selectively emitting linearly-polarized light and non-polarized light, and retardation element disposed between liquid crystal display device and light source unit. Plurality of first and second layers whose slow axes are arranged in different directions are alternately arranged on a surface of retardation element that faces light source unit, and plurality of third and fourth layers whose slow axes are arranged in different directions are arranged on the other surface, such that third layers face first layers and fourth layers face second layers. First to fourth layers are arranged such that polarization plane of light passing through first and third layers and second and fourth layers is rotated by 90&#xb0;, and polarization plane of light passing through first and fourth layers and second and third layers is rotated by 180&#xb0; or 0&#xb0;.

Surface light source for emitting linearly-polarized light whose polarization plane is varied depending on emission direction and view angle changeable liquid crystal display apparatus using same

A display device includes a screen having opposite ends and a curved surface between the opposite ends, the curved surface being protrudingly curved toward a side opposite to a display observation side. First and second display elements are respectively provided at the opposite ends of the screen, and display two different sub-images constituting one image. The display elements are arranged in such a manner that sub-image lights of these sub-images are transmitted toward an inner side from corresponding areas on an outer side of the curved surface in end sections of the screen to be applied to the inner side of the curved surface of the screen and sub-image lights are reflected on the inner surface of the curved surface of the screen to enter right and left eyes of an observer, respectively.

Growing community of inventors

Iruma, Japan

Yasuhiro Daiku