Projection type image display apparatus
Elements of an optical system ( 12 ) of a projection type image display apparatus are stored in an optical system storage ( 46 ) having an upper opening in such a way that the optical element to be arranged close to a light source is fitted in the frame provided in the high-temperature region of the optical system storage ( 46 ) close to the light source, while the rest of the optical elements are respectively fitted in the frames in the low-temperature region of the optical system storage ( 46 ) remote from the light source. The upper opening in the high-temperature region is covered, in the low-temperature region, with a resilient metal lid ( 471 ), and, in the low-temperature region, covered with a resilient resin lid ( 472 ). Portions of these lids are partially cut into spring-like narrow strips having tips configured to firmly and accurately hold the lenses fitted in the respective frames, whereby the dimensional tolerances of the optical elements and the frames can be absorbed solely by the lids without resorting to any other parts.
1. A projection type image display apparatus equipped with an optical system adapted to project modulated imaging light obtained by modulating beams of light emitted from a high-temperature light source based on the image signals received to form an enlarged image on a display screen, said display apparatus comprising an optical system storage for storing said optical system, said optical system storage having:
an upper opening;
a high-temperature region for accommodating an optical element to be arranged proximal to said light source;
a low-temperature region for accommodating optical elements to be arranged distant from said light source, and
a multiplicity of frames arranged in said upper opening, each of said frame having an upper opening for receiving an optical element,
said opening covered, in said high-temperature region, with a resilient metal lid and, in said low-temperature region, with a resilient resin lid.
2. The projection type image display apparatus according to claim 1 , wherein said optical system includes:
at least a first integrator lens, an iris mechanism, a second integrator lens, a slit, a polarization beam splitter, and a condenser lens, all arranged to pass white light received from said light source through said combination in a desired manner;
a multiplicity of dichroic mirrors for splitting the white light that has passed through said condenser lens into red (R), green (G), and blue (B) light;
three liquid crystal panels for respectively extracting R, G, B light;
a color composition prism for composing said R, G, B lights into tri-color imaging light; and
a projection lens for projecting said tri-color imaging light.
3. The projection type image display apparatus according to claim 2 , wherein
said first integrator lens is fitted in the frame in said high-temperature region;
a portion of said metal lid associated with said frame is cut into spring-like narrow strips having V-shaped projecting tips for firmly holding the upper end of said first integrator lens fitted in said frame;
lenses of said optical system other than said first integrator lens are fitted in the respective frames in said low-temperature region; and
portions of said resin lid associated with said respective frames are partially cut into spring-like narrow strips having protruding tips for firmly holding the upper ends of said lenses fitted in said respective frames, whereby
the dimensional tolerances of said lenses and frames are absorbed by said lids.