Optics: image projectors – Housing
Reexamination Certificate
2000-02-01
2002-06-18
Adams, Russell (Department: 2851)
Optics: image projectors
Housing
C353S122000, C353S033000, C349S058000
Reexamination Certificate
active
06406151
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of Invention
The present invention relates to a unit for mounting an electro-optical device, such as a liquid crystal panel, to a prism, such as a dichroic prism or a polarization beam splitter, and to a projection display device using the same.
2. Description of Related Art
An example of a conventional projection display device relating to the present invention in which an electro-optical device, such as a liquid crystal panel, is mounted to a prism is disclosed, for example, in Japanese Unexamined Patent Publication No. 10-10994. Thus, Japanese Unexamined Patent Publication No. 10-10994 will be briefly described with reference to an exploded view of FIG.
16
.
A liquid-crystal-panel unit
70
R is mounted to a light-incident surface
72
R of a prism composition
72
of a projection display device. The panel unit
70
R is composed of an innermost fixed frame body
76
bonded and fixed to the light-incident surface
72
R of the prism composition
72
, an outermost panel frame body
73
for accommodating and holding a liquid crystal panel
80
R, and an intermediate frame body
77
disposed between the fixed frame body
76
and the panel frame body
73
. The panel frame body
73
has a first frame body
74
and a second frame body
75
, and further holds the liquid crystal panel
80
R by sandwiching between these frame bodies
74
and
75
.
Engaging projections
77
b
projected outward from four comers of the intermediate frame body
77
are fitted and bonded into engaging holes
74
b
formed in four comers of the panel frame body
73
(the first frame body
74
thereof), and a spacer
78
having a substantially triangular prism shape is provided between the intermediate frame body
77
and the panel frame body
73
so as to bond and fix the intermediate frame body
77
and the panel frame body
73
.
Process steps for obtaining the above construction will be described hereinbelow with reference to a flow shown in FIG.
17
.
That is, the fixed frame body
76
is first located and fixed on the light-incident surface
72
R of the prism composition
72
by an adhesive agent (S
1
). Then, the intermediate frame body
77
is located outside the bonded and the fixed frame body
76
, and is fixed by inserting four screws
79
into tapped holes
77
a
and
76
a
(S
2
).
Thereafter, an adhesive agent is charged into the engaging holes
74
b
that are formed in the first frame body
74
of the panel frame body
73
in which the liquid crystal panel
80
R is accommodated and held, and the panel frame body
73
is attached to the intermediate frame body
77
by fitting the engaging projections
77
b
of the intermediate frame body
77
into the engaging holes
74
b
(S
3
).
Next, the liquid crystal panel
80
R is turned on in this state (S
4
), and focus adjustment and alignment adjustment of the liquid crystal panel
80
R are performed (S
5
and S
6
). These steps S
4
to S
6
are performed to adjust the position and the inclination of the liquid crystal panel
80
R on the optical axis.
Next, the adhesive agent charged in the engaging holes
74
b
is hardened to temporarily fix the intermediate frame body
77
and the panel frame body
73
(S
7
). Thereafter, a shift amount of the position of pixels of the liquid crystal panel
80
R is checked (S
8
). Consequently, when the shift amount is beyond an allowable range (bad), the panel frame body
73
is removed (S
13
), and the procedure returns to the aforementioned step S
3
.
On the other hand, when the shift amount is within the allowable range (good), the adhesive agent is applied to the spacer
78
(S
9
), and the spacer
78
is mounted to a predetermined guide section formed between the temporarily fixed intermediate frame body
77
and the panel frame body
73
(S
10
). Then,.by hardening the adhesive agent among the spacer
78
, the panel frame body
73
, and the intermediate frame body
77
, the panel frame body
73
is actually fixed to the prism composition
72
(S
11
).
In the case of the above conventional device, however, the panel frame body is temporarily fixed to the prism after adjusting the position of the liquid crystal panel and then actually fixed at a place different from the temporarily fixed place, resulting in a shift of the position of the liquid crystal panel in an actual fixing step.
In addition, a temporary fixing step differs from the actual fixing step in a bonded section, so that there is a problem in that the operation process is complicated, and the working efficiency is low because a hardening period of the adhesive agent is required for each step.
Also, when the adhesive agent is hardened, the panel frame body is susceptible to displacement due to the contraction of the adhesive agent. However, there is a problem in that the number of bonded sections increases because of the temporary fixing, and hardening of the adhesive agent tends to cause a shift of the position of the liquid crystal panel.
Further, the temporary fixing and the actual fixing are performed at different sections, so that there is a high risk of occurrence of shift of the position of the liquid crystal panel under the influence of expansion or contraction by heat generated by the use of a projection display device. For this reason, there is room for improvement in realizing a projection display device which does not cause a shift of the position of the liquid crystal panel for a long period.
Thus, the present invention proposes a unit which can eliminate a temporary fixing step from steps for fixing an electro-optical device, such as a liquid crystal panel, to a prism and which can mount a panel frame body for accommodating and holding the electro-optical device, such as the liquid crystal panel, to the prism only by a spacer section, and a projection display device using the same to thereby achieve an increase in fixing and positioning accuracy of the electro-optical device, an increase in fixing operation efficiency, and simplification of the fixing operation.
SUMMARY OF THE INVENTION
A projection display device is provided having an electro-optical device for modulating light, a prism to which the electro-optical device is mounted, and a projection lens for projecting modulated light. The projection display device may include: a fixed frame plate fixed adjacent to a surface of the prism and a center portion thereof being opened, an electro-optical device frame body for holding the electro-optical device, and a spacer having a plane opposed to the fixed frame plate and a plane opposed to the electro-optical device frame body, and placed between the fixed frame plate and the electro-optical device frame body. The fixed frame plate and the electro-optical device frame body may be bonded and fixed by an adhesive agent via the spacer, and a bonded surface of the fixed frame plate to the spacer may protrude toward the electro-optical device frame body.
In addition, an electro-optical device mounting unit for mounting an electro-optical device for modulating light to a prism, may include: a fixed frame plate fixed adjacent to a surface of the prism and a center portion thereof being opened, an electro-optical device frame body for holding the electro-optical device, and a spacer having a plane opposed to the fixed frame plate and a plane opposed to the electro-optical device frame body, and placed between the fixed frame plate and the electro-optical device frame body. The fixed frame plate and the electro-optical device frame body may be bonded and fixed by an adhesive agent via the spacer, and a bonded surface of the fixed frame plate to the spacer may protrude toward the electro-optical device frame body.
Accordingly, a distance between the effective center of the bonded surfaces of the spacer and the fixed frame plate and the effective center of the bonded surfaces of the spacer and the electro-optical device frame body can be effectively reduced while maintaining the clearance between the prism and the electro-optical device constant, so that the rotational moment exerted on the spacer can be reduced a
Adams Russell
Koval Melissa
Oliff & Berridge PLC.
Seiko Epson Corporation
LandOfFree
Electro-optical device mounting unit and projector using the... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Electro-optical device mounting unit and projector using the..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Electro-optical device mounting unit and projector using the... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2895785