Ricoh Company, Ltd.

Kasumi Nakamura

Yohei Takano

Kazuhiro Fujita

Makoto Hirakawa

Tatsuya Takahashi

Takashi Sasaki

Shigeaki Imai

Naoki Nakamura

Jun Mashimo

Hirotoshi Nakayama

Momotaro Yoshida

A light-source optical system includes a wavelength converter on which light of first color is incident, the wavelength converter converting at least a part of the light of first color into light of second color different from the light of first color, a first optical system disposed upstream from the wavelength converter on an optical path of the light of first color, the first optical system including optical elements, a reflection plane disposed downstream from the first optical system on the optical path, and a second optical system disposed downstream from the reflection plane on the optical path. The reflection plane reflects one of the light of first color and the light of second color, and a conditional expression 0<ΔL/D<0.2 is satisfied.

Light-source optical system, light-source device, and image display apparatus

A light-source device includes an excitation light source, an optical member, and a wavelength converter. The excitation light source is configured to emit first color light. The optical member has a reflecting surface configured to reflect the first color light emitted from the excitation light source. The wavelength converter includes a wavelength conversion member on which the first color light reflected by the optical member is incident. The wavelength conversion member is configured to convert at least part of the first color light into second color light having a wavelength different from a wavelength of the first color light and emit the second color light. A center of the first color light on the reflecting surface of the optical member does not intersect with a light flux of the first color light emitted from the wavelength converter.

Light-source device and image forming apparatus including same

A light source optical system includes: a first optical system configured to guide a first light beam having a first wavelength emitted from a light source to a wavelength conversion element; the wavelength conversion element configured to convert the first light beam into a second light beam having a second wavelength different from the first wavelength, and emit the second light beam; and a second optical system through which the second light beam emitted from the light conversion element passes. The second optical system includes a light guide element configured to guide a portion of the second light beam from one end surface of the light guide element to the other end surface of the light guide element to separate the portion of the second light beam from the second light beam.

Light source optical system, light source device, light source unit, and image display apparatus

A light-source device includes an excitation light source to emit first color light; an optical member having a reflecting surface to reflect the first color light; a wavelength conversion unit including a wavelength conversion member on which the first color light reflected by the optical member is incident, the wavelength conversion member to convert at least part of the first color light into second color light having a wavelength different from a wavelength of the first color light and emit the second color light; and a light condensing element to condense the first color light emitted from the wavelength conversion unit. A straight line including a first optical path from a center of a flux of light rays emitted from the excitation light source, to the center of the first color light on the reflecting surface does not intersect with a light flux condensed by the light condensing element.

Light-source device, image projection apparatus, and light-source optical system

A wavelength conversion plate includes a conversion region and a reflection region on a base surface. The conversion region includes a wavelength conversion member configured to receive excitation light and generate a color different from a color of the excitation light. The reflection region is configured to reflect the excitation light. The reflection region includes a transmissive diffusion surface, a transmissive layer, and a reflection surface. The transmissive diffusion surface is configured to diffuse the excitation light. The transmissive layer is configured to transmit the excitation light. The reflection surface is configured to reflect the excitation light. The transmissive diffusion surface is in a position separate from a surface closer to the base surface, of the wavelength conversion member, toward a direction from which the excitation light is incident.

Wavelength conversion plate, light source device, and image projection apparatus

A light source device includes: a first light source to emit first color light; a second light source to emit second color light; a wavelength conversion unit to convert at least a portion of the first color light into a third color light; a light incident element to which the first color light, the second color light, and the third color light enter; a first filter to reflect the first color light toward the wavelength conversion unit; and a second filter to reflect the second color light toward the light incident element. The first filter and the second filter are separately disposed on an optical path of the third color light between the wavelength conversion unit and the light incident element.

Light source device and image projection apparatus

An image projection apparatus includes a first light source to emit a first excitation light of a specific wavelength, a second light source to emit a second excitation light of a specific wavelength, a first planar wavelength conversion element to convert the first excitation light into a light of a different specific wavelength, and a second planar wavelength conversion element to convert the second excitation light into a light of a specific wavelength different from the specific wavelength of the first excitation light converted by the first planar wavelength conversion element. In the image projection apparatus, the first planar wavelength conversion element and the second planar wavelength conversion element are arranged at positions different from each other, and the first planar wavelength conversion element and the second planar wavelength conversion element have a first plane and a second plane.

Image projection apparatus

A light-source device includes an excitation light source; an optical element having a reflecting surface to reflect first colored light emitted from the excitation light source; and a wavelength conversion unit including a waveform conversion member configured to convert at least a portion of the first colored light reflected by the optical element and incident on the wavelength conversion unit, into second colored light having a wavelength different from a wavelength of the first colored light and emit the second colored light. A point P does not intersect with a light flux Q where the point P is a center of the first colored light on the reflecting surface of the optical element and the light flux Q is a light flux of the first colored light emitted from the wavelength conversion unit.

Light source device and image projection apparatus including a rod integrator and light guide

A light guide optical device includes an optical path combiner including: a first deflector to deflect first light incident from a first direction to an emission direction; a second deflector to deflect second light incident from a second direction different from the first direction, to the emission direction; and a transmission portion between the first deflector and the second deflector, the transmission portion to transmit third light incident from a third direction different from each of the first direction and the second direction, to the emission direction. The optical path combining unit combines the first light, the second light, and the third light, and emits the combined light to the mission direction.

Light guide optical device, light source device, and image projection apparatus

A light-source device includes an excitation light source; a wavelength conversion unit to convert at least some of first color light into second color light; a light mixing element including a rod integrator to mix at least one of the first color light and the second color light from the conversion unit; and an optical element on an optical path of the first color light and having a reflecting surface. A center of the first color light on the reflecting surface intersects with only one of a first light flux of the first color light incident on and a second light flux of the first color light emitted from the conversion unit. An angle formed by a projection straight line of the first color light incident on an incident aperture of the integrator and a predetermined axial line of the incident aperture of the integrator is smaller than 40&#xb0;.

Light-source device and image projection apparatus

A light source optical system includes a wavelength conversion unit configured to receive first color light emitted from by an excitation light source and emit second color light with a wavelength different from a wavelength of the first color light; and a first optical system and a second optical system provided in an optical path between the excitation light source and the wavelength conversion unit. The first optical system includes one optical element having a negative power,

Growing community of inventors

Kanagawa, Japan

Kasumi Nakamura