Projection apparatus

Abstract

A projection apparatus includes an optical engine (10) that projects an image on a screen from a rear side, an engine supporting plate (100) on which the optical engine (10) is placed, an adjusting member (500) of a substantially wedge-shape inserted into between a base portion (11) and a lower surface of the engine supporting plate (100) so that front or rear end of the engine supporting plate (100) is vertically rotatable, a front-to-rear position adjusting unit (56) capable of moving the adjusting member (500) in front-to-rear direction, a slope portion (108) having a slope surface (109) that gradually increases or decreases an angle of a surface of the adjusting member (500) contacting the engine supporting plate (100) in accordance with a movement of the adjusting member (500), and a fixing unit (551, 552) that fixes the engine supporting plate (100) to an adjusted position.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

In the attached drawings:

FIG. 1 is a sectional view of a rear projector having an angle adjusting mechanism of an optical engine according to Embodiment 1 of the present invention;

FIG. 2 is a perspective view of the angle adjusting mechanism for adjusting the angle of an engine supporting plate provided in a rear projector shown in FIG. 1;

FIG. 3A shows a displacement of a projected image toward the upper left with respect to the screen;

FIG. 3B shows a rotational displacement of the projected image in the clockwise direction with respect to the screen;

FIG. 3C shows a trapezoid distortion (vertical keystone distortion) in which a projected image becomes expanded toward the lower side with respect to the screen;

FIG. 3D shows a trapezoid distortion (horizontal keystone distortion) in which a projected image becomes expanded toward the right side with respect to the screen;

FIG. 4 is a perspective view of the angle adjusting mechanism in an initial state before the adjustment of the angle of the engine supporting plate;

FIG. 5 is a side view of the angle adjusting mechanism shown in FIG. 4;

FIG. 6 is a perspective view showing the angle adjusting mechanism rotating the engine supporting plate at an angle θa in a positive (upward) vertical rotating direction θx to adjust the angle in the vertical direction in order to correct the vertical keystone distortion of the projected image;

FIG. 7 is a side view of the angle adjusting mechanism shown in FIG. 6;

FIG. 8 is a perspective view showing the angle adjusting mechanism rotating the engine supporting plate at an angle θb in a negative (downward) vertical rotating direction θx to adjust the angle in the vertical direction in order to correct the vertical keystone distortion of the projected image;

FIG. 9 is a side view of the angle adjusting mechanism shown in FIG. 8;

FIG. 10 is a perspective view showing the angle adjusting mechanism rotating the engine supporting plate counterclockwise in a horizontal rotating direction θz to adjust the angle in the horizontal direction in order to correct the rotation displacement of the projected image;

FIG. 11 is a schematic side view showing the engine supporting plate when the engine supporting plate is rotated upward to a maximum angle as shown in FIG. 7 and when the engine supporting plate is rotated downward to a maximum angle as shown in FIG. 9 together with auxiliary lines, with the vertical scale being enlarged;

FIG. 12 is a side view of the angle adjusting mechanism according to Embodiment 2 of the present invention in an initial state before the adjustment of the angle of the engine supporting plate;

FIG. 13 is a side view showing the angle adjusting mechanism of FIG. 12 rotating the engine supporting plate at an angle θa in a positive (upward) vertical rotating direction θx to adjust the angle in the vertical direction in order to correct the vertical keystone distortion of the projected image;

FIG. 14 is a side view showing the angle adjusting mechanism of FIG. 12 rotating the engine supporting plate at an angle θb in a negative (downward) vertical rotating direction θx to adjust the angle in the vertical direction in order to correct the vertical keystone distortion of the projected image;

FIG. 15 is a side view of the angle adjusting mechanism according to Embodiment 3 of the present invention in an initial state before the adjustment of the angle of the engine supporting plate;

FIG. 16 is a side view showing the angle adjusting mechanism of FIG. 15 rotating the engine supporting plate at an angle θa in a positive (upward) vertical rotating direction θx to adjust the angle in the vertical direction in order to correct the vertical keystone distortion of the projected image;

FIG. 17 is a side view showing the angle adjusting mechanism of FIG. 15 rotating the engine supporting plate at an angle θb in a negative (downward) vertical rotating direction θx to adjust the angle in the vertical direction in order to correct the vertical keystone distortion of the projected image;

FIG. 18 is a side view of the angle adjusting mechanism according to Embodiment 4 of the present invention in an initial state before the adjustment of the angle of the engine supporting plate;

FIG. 19 is a side view showing the angle adjusting mechanism of FIG. 18 rotating the engine supporting plate at an angle θa in a positive (upward) vertical rotating direction θx to adjust the angle in the vertical direction in order to correct the vertical keystone distortion of the projected image;

FIG. 20 is a side view showing the angle adjusting mechanism of FIG. 18 rotating the engine supporting plate at an angle θb in a negative (downward) vertical rotating direction θx to adjust the angle in the vertical direction in order to correct the vertical keystone distortion of the projected image;

FIG. 21 is a side view of the angle adjusting mechanism according to Embodiment 5 of the present invention in an initial state before the adjustment of the angle of the engine supporting plate;

FIG. 22 is a side view showing the angle adjusting mechanism of FIG. 21 rotating the engine supporting plate at an angle θa in a positive (upward) vertical rotating direction θx to adjust the angle in the vertical direction in order to correct the vertical keystone distortion of the projected image; and

FIG. 23 is a side view showing the angle adjusting mechanism of FIG. 21 rotating the engine supporting plate at an angle θb in a negative (downward) vertical rotating direction θx to adjust the angle in the vertical direction in order to correct the vertical keystone distortion of the projected image.

Claims

1. A projection apparatus comprising: a housing;a transmission-type screen provided on a front side of said housing;an optical engine provided in said housing, said optical engine projecting an image on said transmission-type screen from a rear side of said transmission-type screen;an engine supporting plate on which said optical engine is placed, said engine supporting plate being provided in said housing so that an angle of said engine supporting plate is adjusted to thereby adjust a projecting direction of said optical engine;a base portion provided on an inner bottom surface of said housing;an adjusting member having a substantially wedge-shape with nonparallel upper and lower surfaces, said adjusting member being inserted into between said base portion and a lower surface of said engine supporting plate, so that front or rear end of said engine supporting plate is vertically rotatable;a front-to-rear position adjusting unit capable of pushing said adjusting member frontward and pulling said adjusting member rearward;a slope portion having a slope surface that gradually increases or decreases an angle of a surface of said adjusting member that contacts said engine supporting plate in accordance with a movement of said adjusting member in front-to-rear direction, anda fixing unit that fixes said engine supporting plate to an adjusted position.

2. The projection apparatus according to claim 1, wherein said slope surface of said slope portion contacting said adjusting member has an arcuate shape in a longitudinal cross section, wherein a surface of said adjusting member on a side contacting said slope portion has a slidable arcuate shape in a longitudinal cross section corresponding to said arcuate shape of said slope portion, andwherein said arcuate shape has a curvature such that, when said engine supporting plate is rotated in a vertical direction, an angle of a surface of said adjusting member on a side that does not contact said slope surface follows a change in an angle between a lower surface of said engine supporting plate and said base portion.

3. The projection apparatus according to claim 1, wherein said slope portion has a plurality of contact protrusions on a side contacting said adjusting member, said contact protrusions being disposed at different positions in front-to-rear direction and having shapes and positions such that said contact protrusions are able to contact said adjusting member when said adjusting member is moved by said front-to-rear position adjusting member, wherein a surface of said adjusting member on a side contacting said contact protrusions of said slope portion has an arcuate shape in a longitudinal cross section, andwherein said arcuate shape has a curvature such that, when said engine supporting plate is rotated in a vertical direction, an angle of a surface of said adjusting member on a side that does not contact said slope portion follows a change in angle between a lower surface of said engine supporting plate and said base portion.

4. The projection apparatus according to claim 1, wherein said slope surface of said slope portion that contacts said adjusting member has an arcuate shape in a longitudinal cross section, wherein said adjusting member has a plurality of contact protrusions on a side contacting said slope portion, said contact protrusions being disposed at different positions in front-to-rear direction and having shapes and positions such that said contact protrusions are able to contact said slope portion when said adjusting member is moved by said front-to-rear position adjusting member, andwherein said arcuate shape has a curvature such that, when said engine supporting plate is rotated in a vertical direction, an angle of a surface of said adjusting member on a side that does not contact said slope portion follows a change in angle between a lower surface of said engine supporting plate and said base portion.

5. The projection apparatus according to claim 1, wherein said slope portion has convexes and concaves on said slope surface contacting said adjusting member, said convexes and concaves being in the form of a sawtooth continuously formed along an arcuate shape in a longitudinal direction, wherein said adjusting member has convexes and concaves in the form of a sawtooth continuously formed on a side contacting said slope portion, said convexes and concaves of said adjusting member having inverted shapes of said convexes and concaves of said slope portion, andwherein said arcuate shape has a curvature such that, when said engine supporting plate is rotated in a vertical direction, an angle of a surface of said adjusting member on a side that does not contact said slope portion follows a change in angle between a lower surface of said engine supporting plate and said base portion.

6. The projection apparatus according to claim 1, wherein said slope portion is fixed to an upper surface of said base portion provided on said inner bottom surface of said housing, and wherein said adjusting member is slidably moved by said front-to-rear position adjusting unit while contacting said slope surface of said slope portion.

7. The projection apparatus according to claim 1, wherein said slope portion is fixed to a lower surface of said engine supporting plate, and wherein said adjusting member is slidably moved by said front-to-rear position adjusting unit while contacting said slope surface of said slope portion.

8. The projection apparatus according to claim 1, wherein a surface of said adjusting member on a side that does not contact said slope portion is a flat surface.

9. The projection apparatus according to claim 1, wherein said engine supporting plate has a convex-shaped center shaft protrusion at an end thereof opposite to a vertically rotated end, and wherein said base portion has a center shaft receiving portion in the form of a concave or through-hole capable of receiving said center shaft protrusion.

10. The projection apparatus according to claim 1, wherein said base portion has a convex-shaped center shaft protrusion at a position facing an end of said engine supporting plate opposite to a vertically rotated end, and wherein said engine supporting plate has a center shaft receiving portion in the form of a concave or through-hole capable of receiving said center shaft protrusion.

11. The projection apparatus according to claim 9, wherein said center shaft protrusion has a shape such that said center shaft protrusion functions as a rotational axis in vertical and horizontal directions, and has a dimension such that said center shaft protrusion can be inserted into said center shaft receiving portion, and wherein said center shaft receiving portion has shape and dimension such that said center shaft receiving portion is able to receive said center shaft protrusion.

12. The projection apparatus according to claim 11, wherein said center shaft protrusion is provided on a front end of said engine supporting plate, and wherein said center shaft receiving portion is provided on said base portion.

13. The projection apparatus comprising: an optical engine that projects an image;an optical engine placing unit on which said optical engine is placed;a supporting unit supporting said optical engine placing unit so that said optical engine placing unit is rotatable about a predetermined axis, andan adjusting unit rotating said optical engine placing unit about said predetermined axis, to thereby adjust a projecting direction of said optical engine,wherein said adjusting unit comprises:an adjusting member having an arcuate surface having a center at a predetermined point, anda guide portion that guides said adjusting member along said arcuate surface.