PROJECTION TYPE TABLE DISPLAY

• US 20100245685A1
• Filed: 12/23/2009
• Published: 09/30/2010
• Est. Priority Date: 03/31/2009
• Status: Active Grant

• Current Assignee: Maxell, Ltd.
• Original Assignee: Hitachi Consumer Electronics Company Limited (Hitachi, Ltd.)
• Inventors: Ishikawa, Tatsuya, ONODERA, Shinji, Mukai, Yusuke, Morishita, Satomi
• Granted Patent: US 8,314,894 B2
• Time in Patent Office: Days
• US Class Current: 348/745
• CPC Class Codes: G03B 21/006 using LCD's
• CPC Class Codes: H04N 9/3185 Geometric adjustment, e.g. keystone or convergence optical or mechanical adjustment of convergence H04N9/317; using scanning means H04N3/22; optical or mechanical adjustments of projectors not peculiar to the presence of an electronic spatial light modulator G03B21/14

Abstract

In the usage of table projection of a projection type display, depending upon a sitting position of a participant of a conference, the participant views an image projected upon a table as an inversion image turned upside down, resulting in poor visual recognition. In order to improve visual recognition, images are rotated, synthesized and displayed in accordance with the viewing direction of each participant. More specifically, the projection type display is provided with a two-image synthesizing unit for synthesizing two images obtained by processing an input image by two image rotation units for rotating the input image by a first angle and a second angle different from the first angle, into one image on a screen. The projection type display is also provided with an image rotation unit and an image inversion unit for two-image display on a screen.

Claims

1. A projection type display comprising:

an image processing unit for processing an input image;

an illumination optical block for radiating an optical beam;

a liquid crystal panel for modulating the optical beam radiated from said illumination optical block with an output signal from said image processing unit and outputting the modulated optical beam; and

a projection lens block for projecting the modulated optical beam output from said liquid crystal panel upon a projection object,

wherein said image processing unit comprises;

a first image rotation unit for rotating the input image by a first angle;

a second image rotation unit for rotating the input image by a second angle; and

a two-image synthesizing unit for synthesizing a first output image from said first image rotation unit and a second output image from said second image rotation unit into one image.

2. The projection type display according to claim 1, wherein said image processing unit executes a scaling process including magnification, reduction and geometrical distortion correction of an output image output from said two-image synthesizing unit.

3. The projection type display according to claim 1, wherein said first image rotation unit or said second image rotation unit executes a scaling process including magnification and reduction of an input image.

4. The projection type display according to claim 3, wherein said first image rotation unit or said second image rotation unit executes a scaling process including magnification, reduction and geometrical distortion correction of an output image from said two-image synthesizing unit.

5. The projection type display according to claim 1, wherein said two-image synthesizing unit executes a scaling process including magnification and reduction of a first output image from said first image rotation unit and a second output image from said second image rotation unit, respectively, and thereafter, performs image synthesis.

6. The projection type display according to claim 5, wherein said image processing unit executes a scaling process including magnification, reduction and geometrical distortion correction of an output image from said two-image synthesizing unit.

7. The projection type display according to claim 1, wherein said first angle and said second angle have a difference of 180 degrees.

8. The projection type display according to claim 1, wherein said first angle is 90 degrees in the clockwise direction.

9. The projection type display according to claim 1, wherein if an optical beam output from said projection lens block is projected upon a generally vertical flat plane of the projection object, one image on a screen is output from said image processing unit.

10. The projection type display according to claim 9, further comprising an operation unit for receiving a user operation, wherein in response to a signal from said operation unit, an output image from said image processing unit is switched between an output image of one image on a screen and an output image of two images on a screen.

11. The projection type display according to claim 9, further comprising an angle sensor for detecting an installation angle of said projection type display or a posture angle of said projection type display, or for detecting an angle of said projection lens block or an angle of an optical beam output from said projection lens block, wherein in response to a signal from said angle sensor, an output image from said image processing unit is switched between an output image of one image on a screen and an output image of two images on a screen.

12. A projection type display for optically modulating an optical beam from a light source with image information and projecting the modulated optical beam, comprising:

an image rotation unit for executing a 90-degree rotation process for an input image;

an image inversion unit for inverting image information upside down;

an image memory for memorizing processing results by said image rotation unit and by said image inversion unit to store the image information;

a drive circuit for reading the image information from said image memory to control the optical modulation;

a liquid crystal panel for performing the optical modulation of the optical beam; and

a projection lens block for magnifying and displaying the modulated optical beam.

13. The projection type display according to claim 12, further comprising a user position detection unit for detecting a position of a user viewing a display image by the projection type display, wherein in accordance with a detection result of said user position detection unit, said image rotation unit or said image inversion unit processes the input image to perform two-image display along an up-down direction or two-image display side by side along a right/left direction.

14. The projection type display according to claim 13, wherein if said user position detection unit detects users along a long side direction of a projection area, two-image display along an up-down direction is performed by disposing along the long side direction of the projection area an image obtained by rotating the input image by said image rotation unit and an image obtained by inverting the image rotated by said image rotation unit.

15. The projection type display according to claim 13, wherein if said user position detection unit detects users along a short side direction of a projection area, two-image display side by side along a right/left direction is performed by disposing along the long side direction of the projection area the input image and an image obtained by inverting the input image.

16. The projection type display according to claim 12, further comprising a user position detection unit for detecting a position of a user viewing a display image by the projection type display, wherein in accordance with a detection result of said user position detection unit, said image rotation unit or said image inversion unit processes the input image so as to display an erection image as viewed by a user.