News Column

Patent Issued for Light Source Apparatus and Projector

September 10, 2014

By a News Reporter-Staff News Editor at Journal of Engineering -- According to news reporting originating from Alexandria, Virginia, by VerticalNews journalists, a patent by the inventor Sato, Makoto (Tachikawa, JP), filed on March 6, 2012, was published online on August 26, 2014.

The assignee for this patent, patent number 8814366, is Casio Computer Co., Ltd. (Tokyo, JP).

Reporters obtained the following quote from the background information supplied by the inventors: "The present invention relates to a light source apparatus and a projector.

"In these days, data projectors are used on many occasions as image projection units which project images including images of screens of personal computers and video images, as well as images based on image data which is stored in memory cards on to a screen. In these projectors, light emitted from a light source is collected on to a micromirror display device called a digital micromirror device (DMD) or a liquid crystal plate for projection of color images on to a screen.

"As the use of imaging equipment such as personal computers and DVD players has spread, the application of such data projectors has spread from the business or commercial use, for example, in which they are used as means for presentation to the domestic use. Conventionally, the mainstream of these projectors has been those which use a high-intensity discharge lamp as a light source. However, in recent years, there have been made many developments and proposals on data projectors which use, as a light source, semiconductor light emitting elements such as LEDs and laser diodes.

"Then, for example, Japanese Unexamined Patent Publication No. 2007-157548 (JP-A-2007-157548) discloses a light source apparatus which enhances the light utilization efficiency by taking into consideration luminous intensity distribution characteristics which change based on shapes of red, green and blue LED chips and colors of light emitted therefrom and a projector which includes the light source apparatus.

"The projector disclosed in JP-A-2007-157548 is such that light emitted from the LED chips is guided to a light guiding device of a predetermined length by adjusting the luminous intensity distribution characteristics of light of the respective colors emitted from the LED chips using luminous intensity distribution members which differ according to the luminous intensity distribution characteristics of the light of the respective colors so emitted so as to enhance the efficiency of utilization of light. However, the projector is not designed to suppress the occurrence of unevenness in illuminance of light in a predetermined plane on to which the light is shone from the light guiding device."

In addition to obtaining background information on this patent, VerticalNews editors also obtained the inventor's summary information for this patent: "According to a first aspect of the invention, there is provided a light source apparatus including:

"a plurality of light sources which illuminate light of different wavelength bands and different luminous intensity distributions;

"groups of collective lenses which respectively collect light from the plurality of light sources;

"a light guiding device which is disposed on an axis of light collected together from the plurality of light sources and is adapted to distribute uniformly the illuminance of the light collected from the plurality of light sources;

"a light guiding optical system which collects the light collected from the plurality of light sources to the same optical axis to illuminate the light on to an entrance port of the light guiding device;

"a diffuse plate wheel which is disposed at the entrance port of the light guiding device and which includes a plurality of segments of different coefficients of diffusion which are arranged in a circumferential direction;

"a motor for rotating the diffuse plate wheel; and

"a light source control device which controls the rotation of the diffuse plate wheel in synchronism with the illumination of the plurality of light sources.

"In addition, according to a second aspect of the invention, there is provided a projector including:

"a light source apparatus;

"a display device;

"a light source side optical system which guides light emitted from the light source apparatus to the display device;

"a projection side optical system which projects an image emitted from the display device on to a screen; and

"a projector control unit which controls the light source apparatus and the display device, wherein

"the light source apparatus is the light source apparatus set forth in claim 1 which includes a light source which emits light of red wavelength band, a light source which emits light of blue wavelength band and a light source which emits light of green wavelength band as the plurality of light sources.

"Advantages of the invention will be set forth in the following detailed description of the invention or will be obvious in part from the description. Alternatively, the advantages may be learned through practice of the invention. The advantages of the invention may be realized or obtained by instrumentalities or combinations thereof which will be described in the following description."

For more information, see this patent: Sato, Makoto. Light Source Apparatus and Projector. U.S. Patent Number 8814366, filed March 6, 2012, and published online on August 26, 2014. Patent URL:

Keywords for this news article include: Casio Computer Co., Casio Computer Co. Ltd.

Our reports deliver fact-based news of research and discoveries from around the world. Copyright 2014, NewsRx LLC

For more stories covering the world of technology, please see HispanicBusiness' Tech Channel

Source: Journal of Engineering

Story Tools Facebook Linkedin Twitter RSS Feed Email Alerts & Newsletters