Denso Corporation

Nippon Soken, Inc.

Other

Kenichiro Takada

Tomoyuki Kanda

Tooru Matsumoto

Katsuyoshi Nishii

Hidekazu Hattori

Masahiro Shiozawa

Kazunori Suzuki

Atsuo Ishizuka

Ken Hanashi

Kazumasa Kurokawa

Yasuhiro Mizutani

Satoshi Koike

Takayuki Takeuchi

Kazutoshi Koie

Katsumi Kamiya

A spark plug for an internal combustion engine is provided which includes a hollow cylindrical metal shell with an open end portion to be exposed to a combustion chamber of the engine, a ground electrode joined to the metal shell, a center electrode disposed in the metal housing to define a spark gap between itself and the ground electrode. The spark plug also includes a stream shaper or a stream reflector geometrically formed on the metal shell and/or the porcelain insulator to shape a vortex steam of air-fuel mixture into a stream thereof which is oriented outside the spark plug or serves to decrease the amount of the air-fuel mixture into a pocket between the metal shell and the porcelain insulator. This ensures the stability of ignition of the air-fuel mixture.

Spark plug with slant peripheral surface

A spark plug for an internal combustion engine and related manufacturing method are disclosed having a metal shell, a porcelain insulator, a center electrode and a ground electrode. The center electrode includes a substantially columnar shaped base material body, and a substantially square shaped rod-like Ir alloy tip bonded to a leading end portion of the base material body. The leading end portion has a diameter Dsmaller than a diameter Dof the base material body. The Ir alloy tip has a square shape with a long diagonal line supposed to form a diameter A of a circumscribed circle Cof the Ir alloy tip whose inscribed circle Cis coaxial with the circumscribed circle Cand has a diameter B, with four diameters A, B, Dand Dlay in the relationship expressed as D&#x3e;A&#x3e;D&#x3e;B.

Spark plug for internal combustion engine and related manufacturing method

A hologram screendisplays an image by diffracting and scattering image lightprojected from an image projection apparatus. An upward/downward light scattering device, which scatters light incident from an upward/downward specific angle range spreading obliquely upward or downward, is placed on the image projection apparatus side of a hologram devicein the hologram screen. A leftward/rightward light scattering device, which scatters light incident from a leftward/rightward specific angle range spreading obliquely leftward and rightward, is placed between the hologram deviceand the scattering device. The construction is such that the upward/downward specific angle range contains the incidence angle of the image lighton the hologram screen, and thus provides a hologram screen having good color reproducibility and which permits viewing of the background.

Hologram screen and hologram display

In a hologram screen for reproducing an image based on an output light obtained by scattering and diffusing an image light from an image projector, when a white light (image light) is projected on the hologram screen; and when a distance between two points at optional two points A and B on a surface of the hologram screen is given by 20 cm or less, and a value of the CIE 1976 chromaticity coordinate (u', v&#x2032;) at the point A is given by (u&#x2032;, v&#x2032;) and the value of the CIE 1976 chromaticity coordinate (u&#x2032;, v&#x2032;) at the point B is given by (u&#x2032;, v&#x2032;); the output light perpendicularly from the surface of the hologram screen has a color distribution in which a color difference &#x394;u&#x2032;v&#x2032;between two points A and B is derived from the following formula (1) and given by 0.06 or less, where, the formula (1) is expressed by,&#x394;&#x2032;=[()+()]&#x2003;&#x2003;(1) Further, the output light, which is output to a viewpoint defined by the following formula (2) from the surface of the hologram screen, has the color distribution in which a color difference &#x394;u&#x2032;v&#x2032; between two points A and B is derived from the above formula (1) and given by 0.01 or less, where, the formula (2) is expressed by,/2&#x2003;&#x2003;(2)in the formula (2), L is a distance between the viewpoint and a center of the hologram screen, and H is a length of the hologram screen in the direction of the height.

Hologram screen and a method of producing the same

A method of fabricating a hologram screen having a large visual range and a hologram imaging apparatus used for the particular method of fabricating the hologram screen are disclosed. A plurality of mirrors () extended toward a plurality of photosensitive members () are arranged at a plurality of end portions (), respectively, of a light diffuser (). At least a reference beam () and object beams () passed through the light diffuser () are radiated on a plurality of the photosensitive members () individually thereby to form a plurality of holograms. These holograms are integrated with each other by being arranged two-dimensionally thereby to fabricate a hologram screen. Among the mirrors (), a reference beam-side mirror () arranged nearer to the light source of the reference beams () is extended from the light diffuser () by a length varied with the position of the photosensitive member () to be exposed.

Method of fabricating hologram screen and hologram imaging apparatus

The present invention provides a hologram screen which is capable of preventing separation, and damage to, a hologram film and which permits the hologram film to be reused easily. The present invention relates to a hologram screen that is comprised of a hologram film having the function of diffracting the light projected from a projector, and first and second transparent members that together sandwich the hologram film from the front and back surfaces thereof so as to cover the same.

Hologram screen

A display apparatus according to one aspect of the first invention includes: an irradiating unit for generating signal light which records information to be displayed; a light-transmitting type screen (or hologram screen) which transmits the signal light input by the irradiating unit to an observer; and a reflection preventing member provided to either both sides, i.e., observer's side and rear side, or any one side, of the light-transmitting type screen (or hologram screen). Further, an image input apparatus according to the second invention used in the above display apparatus includes: an irradiating unit for generating signal light which records information to be displayed; a display unit for projecting the signal light irradiated by the irradiating unit; an image input unit for inputting an desired object which exists at another side of the display unit, through the display unit from one side of the display unit, as an image signal; and a noise eliminating unit for eliminating at least a part of image component except for the desired object.

Display apparatus and an image input apparatus used for the same

Method for producing a hologram and a display device using the same

A hologram of an increased size using a single color laser, capable of executing a full color regeneration in a desired view angle and a method for producing the hologram. A plurality of photo-sensitive members are independently exposed to obtain respective holograms, which are connected by using an adhesive layer,constructing a connecting means, in order to obtain an integrated hologram expanded in two-dimensional direction. The holograms are obtained by an interference of a reference light,and an object light passed through a light diffusing body,in order to cause the light diffusing body,to be recorded on the photo-sensitive member. The size of the light diffusing body,is such that the spectral characteristic of the diffused light from the hologram can attain a desired efficiency at least over the entire wavelength range of the visible light.

Hologram device and method for producing the same

A hologram display has a projector (,), a hologram screen (,), and a filter set (,) that is arranged between the projector and the hologram screen to absorb light with a peak diffraction efficiency in a specific wavelength area. The hologram display faithfully reproduces original colors and improves productivity. Also provided is a hologram screen having a hologram element (,) for diffracting and scattering a projected beam (,) from a projector (,), and a light scattering element (,) whose scattering angle is at least five degrees. The hologram screen correctly reproduces original colors.

Hologram display

A method for producing a hologram recording an interference fringe formed by an object light and a reference light on a photosensitive dry plate, and the object light either having diffusing and scattering characteristics or being passed through an optical diffusion body, mainly includes the following steps: In a first step, a ratio .eta..sub.R0 /.eta..sub.00 of a first diffraction efficiency .eta..sub.00 and a second diffraction efficiency .eta..sub.R0, is calculated. The diffraction efficiency .eta..sub.00 is dependent on two object light beams. The efficiency .eta..sub.R0 is dependent on the object light and the reference light. In a second step, the intensity E.sub.O of the object light and the intensity E.sub.R of the reference light is adjusted in such a way that the ratio .eta..sub.R0 /.eta..sub.00 is set to at least 10 and the efficiency .eta..sub.00 does not exceed 5%. A display device using the above hologram is structured by a display unit for generating a signal light; a hologram screen formed by either reflection or transmission hologram, and a projecting unit for projecting the signal light to the hologram screen. According to the present invention, it is possible to easily produce a hologram, for example, a screen hologram, having no cloudiness or cloudy state when an observer observes an image displayed on the screen, and to a display device using the above hologram screen.

A hologram of an increased size using a single color laser, capable of executing a full color regeneration in a desired view angle and a method for producing the hologram. A plurality of photo-sensitive members are independently exposed to obtain respective holograms, which are connected by using an adhesive layer 80 constructing a connecting means, in order to obtain an integrated hologram expanded in two-dimensional direction. The holograms are obtained by an interference of a reference light 22 and an object light passed through a light diffusing body 24 in order to cause the light diffusing body 24 to be recorded on the photo-sensitive member. The size of the light diffusing body 24 is such that the spectral characteristic of the diffused light from the hologram can attain a desired efficiency at least over the entire wavelength range of the visible light.

Growing community of inventors

Kuwana, Japan

Kenichiro Takada