Granted Patent B2

US 12,483,001 · App. 18/088,022 · Granted Nov 25, 2025

Inventors: Aya Kurita (Osaka, JP); Hirokazu Sakaguchi (Osaka, JP)

Assignee: PANASONIC PROJECTOR & DISPLAY CORPORATION

H01S3/2383G03B21/2013G03B21/2033G03B33/06H01S3/0071G02B27/286

Abstract

Claims (43)

1 . A lighting optical system comprising:

a light source including a plurality of multi-emitter laser chips arrayed in a first direction that intersects a light output direction, the plurality of multi-emitter laser chips each having a first emitter outputting first emitter light and a second emitter outputting second emitter light;

a plurality of convex lenses each having a center between the first emitter and the second emitter of each of the multi-emitter laser chips, the plurality of convex lenses each arranged in close proximity to a corresponding one of the multi-emitter laser chips;

a first refractive element arranged on light output direction side with respect to the plurality of convex lenses, the first refractive element having a first surface receiving two or more first emitter lights output from the plurality of multi-emitter laser chips and a second surface receiving two or more second emitter lights output from the plurality of multi-emitter laser chips; and

a second refractive element arranged on an optical path between the convex lenses and the first refractive element, the second refractive element having a longer focal length than the convex lenses have.

2 . The lighting optical system of claim 1 , wherein

the first refractive element is arranged within a range where a distance x from the light source satisfies a formula below

x≥d /tan θ

where:

d is a distance between an optical axis and a center of an outermost multi-emitter laser chip farthest from an optical axis, of the plurality of multi-emitter laser chips; and

θ is an angle defined between the light output direction and the first or the second emitter light output from the convex lenses.

3 . The lighting optical system of claim 1 , wherein

the first refractive element is arranged within a range where a distance x from the light source satisfies a formula below

x≥d /tan(tan−1 d/f +θ)

where:

f is a focal length of the second refractive element;

d is a distance between an optical axis and a center of an outermost multi-emitter laser chip farthest from an optical axis, of the plurality of multi-emitter laser chips; and

θ is an angle defined between the light output direction and the first or the second emitter light output from the convex lenses.

4 . The lighting optical system of claim 1 , further comprising:

a first mirror and a second mirror that reflect lights from a half and another half, respectively, of the plurality of multi-emitter laser chips of the light source;

a third mirror that reflects lights reflected by the first mirror in the light output direction, to turn the lights into S-polarized lights;

a half-wave plate arranged between the second mirror and the first refractive element, to turn lights reflected by the second mirror into P-polarized lights; and

a polarization beam splitter that combines the S-polarized lights reflected by the third mirror and the P-polarized lights reflected by the second mirror and having passed through the half-wave plate, toward the first refractive element.

5 . The lighting optical system of claim 1 , wherein

the plurality of multi-emitter laser chips each have a third emitter outputting third emitter light between the first emitter and the second emitter, wherein

each third emitter light is output by a corresponding one of the convex lenses along the light output direction, and wherein

the first refractive element has a third surface receiving the third emitter light between the first surface and the second surface.

6 . The lighting optical system of claim 1 , wherein

the multi-emitter laser chips of the light source each have the first emitter and the second emitter arranged along the first direction.

7 . The lighting optical system of claim 1 , further comprising:

a third refractive element arranged on an optical path between the convex lenses and the first refractive element, the third refractive element including a plurality of lenses combined, the third refractive element forming an optical reduction system that reduces width of luminous fluxes from the convex lenses.

8 . The lighting optical system of claim 7 , wherein

the light source is a first light source outputting light of a first wavelength,

the lighting optical system further comprising:

a second light source outputting light of a second wavelength different from the first wavelength;

a third light source outputting light of a third wavelength different from the first and the second wavelengths; and

a combining optical system that combines light of the first wavelength output from the first light source, light of the second wavelength output from the second light source, and light of the third wavelength output from the third light source, into lights having an identical optical axis.

9 . The lighting optical system of claim 1 , wherein

the light source includes the plurality of multi-emitter laser chips arranged both in the first direction and in a second direction intersecting the light output direction.

10 . The lighting optical system of claim 1 , further comprising:

an optical fiber condenser lens that gathers lights from the light source to direct the lights upon an optical fiber.

11 . A projection type display device comprising the lighting optical system of claim 1 .

12 . The lighting optical system of claim 1 , wherein the first refractive element brings the first emitter light and the second emitter light close in parallel.

Assignments (2)

Priority Claims (2)

Continuity (1)

References Cited (19)