US Patent No. 9,575,403

ILLUMINATION OPTICAL SYSTEM, PROJECTOR, AND PROJECTOR SYSTEM


Patent No. 9,575,403
Issue Date February 21, 2017
Title Illumination Optical System, Projector, And Projector System
Inventorship Eisaku Shouji, Tokyo (JP)
Assignee NEC Display Solutions, Ltd., Tokyo (JP)

Claim of US Patent No. 9,575,403

1. An illumination optical system comprising:
a first lens that condenses a first luminous flux that is emitted from a first optical fiber with a first angle of divergence;
a second lens that condenses second luminous flux that has a color that is different from a color of said first luminous flux
and that is emitted from a second optical fiber with a second angle of divergence that differs from said first angle of divergence;
and

a synthesizing optical element that is provided at a position at which an optical axis of said first lens intersects with
an optical axis of said second lens at a right angle, that transmits said first luminous flux from said first lens and that
reflects said second luminous flux from said second lens in a direction in which said first luminous flux was transmitted;

wherein said first and second lenses are configured such that a convergent angle of said first luminous flux that was condensed
by said first lens coincides with a convergent angle of said second luminous flux that was condensed by said second lens,

wherein said first lens is configured such that the following relation is satisfied:
sin ?1/sin ?3=?1and said second lens is configured such that the following relation is satisfied:
sin ?2/sin ?3=?2where ?1 and ?2 are the magnifications of said first and second lenses, respectively, ?1 and ?2 are said first and second
angles of divergence, respectively, and the convergent angle of said first luminous flux that has been condensed by said first
lens and the convergent angle of said second luminous flux that has been condensed by said second lens are both ?3.