Nobuo Sakuma, Seizo Suzuki, Hiromichi Atsuumi, Takeshi Ueda, Yasutaka Izumi: Edge emitting type light emitting diode array heads. Ricoh Company, Woodcock Washburn Kurtz Mackiewicz & Norris, February 25, 1997: US05606181 (98 worldwide citation)

An LED array head comprises a plurality of LED elements and a reflecting element, wherein the reflecting element directs luminous flux emitted from the LED element in a direction substantially perpendicular to the luminous flux emitting direction.

Atsushi Takaura, Kazuhiro Fujita, Nobuo Sakuma: Projection optical system, magnification projection optical system, magnification projection apparatus, and image projection apparatus. Ricoh Company, Oblon Spivak McClelland Maier & Neustadt P C, May 23, 2006: US07048388 (60 worldwide citation)

A projection optical system guiding and projecting a light beam from a projected object surface onto a projection surface in an upstream-downstream direction through a transmission dioptric system and a reflection dioptric system. An intermediate image surface of the projected object surface is posi ...

Seizo Suzuki, Nobuo Sakuma, Katsumi Yamaguchi, Osamu Endo: Optical scanning system. Ricoh Company, Oblon Spivak McClelland Maier & Neustadt, April 9, 1991: US05005928 (46 worldwide citation)

An optical scanning system includes a light source, a coupling lens, a polygon mirror, an f.theta. lens, and a barrel toroidal lens. The barrel toroidal lens includes a barrel toroidal surface in which the radius of curvature thereof measured in the sub-scanning direction decreases with an increased ...

Hiromichi Atsuumi, Nobuo Sakuma, Osamu Endou: Optical scanner having an image forming mirror and means for reducing scanning line pitch irregularities. Ricoh Company, Oblon Spivak McClelland Maier & Neustadt, April 18, 1995: US05408095 (38 worldwide citation)

In an optical scanner, a light source emits a light beam and a coupling lens changes this light beam to a convergent, divergent or parallel light beam. An optical deflector deflects the light beam from the coupling lens at an equal angular velocity. The deflected light beam is converged onto a scann ...

Nobuo Sakuma, Makoto Obu, Akira Momose: Virtual screen display device. Ricoh Company, Greenberg Traurig, September 18, 2001: US06292305 (36 worldwide citation)

A virtual screen display apparatus includes a display arranged to generate display information and having an effective diagonal length DLC and an optical projecting element arranged to receive the display information from the display and to project and form an image, the optical projecting element h ...

Nobuo Sakuma, Hiromichi Atsuumi, Osamu Endou: Image forming reflecting mirror for constant speed optical scan and optical scanner. Ricoh Company, Oblon Spivak McClelland Maier & Neustadt, August 3, 1993: US05233454 (34 worldwide citation)

In an image forming reflecting mirror for a constant speed optical scan, a light beam is convergent in a cross scan-corresponding direction with a point near a starting point of deflection as a starting point of the light beam, and the light beam is deflected at an equal angular velocity and is conv ...

Nobuo Sakuma: Slit illumination system for copying machine. Ricoh, Frank J Jordon, September 21, 1976: US03982116 (28 worldwide citation)

In an electrostatic copying machine, an original document is scanned by moving an original document over an illuminated slit. The system for illuminating the slit comprises an elongated light source and a first elliptic cylindrical mirror having a focus coincident with the axis of the light source t ...

Nobuo Sakuma, Katsumi Yamaguchi: Light beam scanning lens and light beam scanning device. Ricoh Company, Oblon Spivak McClelland Maier & Neustadt, June 19, 1990: US04934772 (27 worldwide citation)

A light beam scanning device has a light source, a condenser optical system, a light beam deflector, and a light beam scanning lens. The light source radiates a light beam which is converted by the condenser optical system. The convergent light beam is then deflected at a constant angular velocity b ...

Osamu Endou, Nobuo Sakuma: Scanning lens and scanning apparatus using scanning lens. Ricoh Company, Cooper & Dunham, July 7, 1992: US05128795 (26 worldwide citation)

A scanning apparatus comprises a light source for emitting a light along an optical axis, a focusing lens for converting the light emitted from the light source into a convergent light, a deflector for deflecting the convergent light from the focusing lens so that a deflected light is scanned at a s ...

Nobuo Sakuma: Two-element f.theta. lens group capable of correcting leaning of deflecting plane. Ricoh Company, Oblon Fisher Spivak McClelland & Maier, February 18, 1986: US04571035 (26 worldwide citation)

An f.theta. lens is provided for use in an optical scanner including a deflection unit for deflecting a beam of light at substantially uniform angular rate, first optics for causing the inciddence of a beam which is elliptical in cross section and has a principal axis substantially parallel to a def ...