US Patent No. 9,904,151

PROJECTOR AND IMAGE PROJECTION METHOD


Patent No. 9,904,151
Issue Date February 27, 2018
Title Projector And Image Projection Method
Inventorship Noriko Nagase, Tokyo (JP)
Atsushi Kato, Tokyo (JP)
Isao Takahashi, Tokyo (JP)
Takashi Ishikawa, Tokyo (JP)
Hirotaka Koyama, Tokyo (JP)
Assignee NEC DISPLAY SOLUTIONS, LTD., Tokyo (JP)

Claim of US Patent No. 9,904,151

1. A projector, comprising:
a plurality of image-forming elements that are each provided with an image-forming surface including a plurality of micromirrors;
a plurality of reflecting elements that are provided so as to reflect respective plurality of image beams that are formed
by said plurality of image-forming elements;

a beam-combining element into which said plurality of image beams are irradiated by said plurality of reflecting elements
and that emits a combined image beam in which said plurality of image beams are combined such that directions of propagation
of said plurality of image beams coincide; and

a projection unit that projects said combined image beam that is emitted by said beam-combining element,
wherein, of said plurality of image forming elements, at least two image-forming elements are arranged such that said image-forming
surface of each image-forming element is located in a same plane,

wherein said plurality of image-forming elements include first to third digital micromirror devices, and
wherein said beam-combining element includes:
an emission surface;
a first incident surface into which an image beam of a first color is irradiated from said first digital micromirror device;
a second incident surface into which an image beam of a second color is irradiated from said second digital micromirror device;
a third incident surface into which an image beam of a third color is irradiated from said third digital micromirror device;
a first dichroic film that is configured to transmit an image beam of said first color that is irradiated from said first
incident surface and emit the image beam from said emission surface, reflect an image beam of said second color that is irradiated
from said second incident surface and emit the image beam from said emission surface, and transmit an image beam of said third
color that is irradiated from said third incident surface; and

a second dichroic film that is configured to transmit an image beam of said first color that is irradiated from said first
incident surface and emit the image beam from said emission surface, reflect an image beam of said third color that is irradiated
from said third incident surface and emit the image beam from said emission surface, and transmit an image beam of said second
color that is irradiated from said second incident surface.