Anti-glare device for projector

• US 6,945,653 B2
• Filed: 07/15/2003
• Issued: 09/20/2005
• Est. Priority Date: 02/21/2003
• Status: Expired due to Term

• Current Assignee: Maxell, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Kobori, Tomoki, Haruna, Fumio, Nozawa, Tsuneyuki
• Primary Examiner(s): Fuller, Rodney
• Assistant Examiner(s): Cruz, Magda
• Application Number:
  US10/619,168
• Publication Number:
  US 20040165154A1
• Time in Patent Office: 798 Days
• Field of Search: 353/69, 353/25, 353/30, 353/122, 382/291, 382/181, 382/190, 382/203, 382/292, 345/2.2, 345/156
• US Class Current: 353/30
• CPC Class Codes: G03B 21/26 Projecting separately subsidiary matter simultaneously with main image
• CPC Class Codes: H04N 5/74 Projection arrangements for image reproduction, e.g. using eidophor
• CPC Class Codes: H04N 9/3194 including sensor feedback
• CPC Class Codes: Y10S 362/80 Light emitting diode

Abstract

There is provided a safe image display apparatus for projecting an image on a screen that can minimize a stimulus to eyes, retinae and optic nerves from projected light entering into the eyes directly. By comparing a displayed image captured by a camera with an input image signal, a changed area is detected as a difference area and, then, a projected image signal is generated wherein a picture area image signal in the input image signal that corresponds to this difference area is masked by a black signal. The obtained projected image signal is projected onto the screen.

Claims

1. A projector type display apparatus for applying light from a light source to a picture display device and projecting outgoing light from said picture display device onto a screen in an enlarged manner comprising:

a display device controller which controls said picture display device based on an input image signal;

a camera which captures an image projected on said screen;

a capture timing controller which controls timing of capture of the image by said camera;

a detector which detects an area projected on said screen;

an image size controller which changes, based on detection results from said detector, the captured image from said camera into a predetermined image size; and

an extractor which comprises a comparator which compares a signal of said captured image the size of which is changed by said image size controller with the image signal input to said display device controller and extracts an area of the captured image corresponding to a person in said captured image;

wherein;

said display device controller controls said picture display device so that an area of an image produced on said image display device corresponding to the extracted person area is modified in accordance with predetermined data, and

said display device controller controls said picture display device based on the image signal input to said display device controller, at least during a period when said camera captures an image projected onto said screen.

2. A projector type display apparatus according to claim 1, wherein said predetermined data is either particular uniform color data, black data or image data having a low intensity level, superimposed on said image signal input to said display device controller.

3. A projector type display apparatus according to claim 1, wherein said extractor further comprises a motion detector which detects a motion area from the captured image data out of the projected area.

4. A projector type display apparatus according to claim 1, wherein said capture timing controller is configured to determine a capture interval and a capture exposure time based on cumulative light intensity for a predetermined time period.

5. A projector type display apparatus for applying light from a light source to a picture display device and projecting outgoing light from said picture display device onto a screen in an enlarged manner comprising:

a display device controller which controls said picture display device based on an input image signal;

a camera which captures an image projected on said screen;

a capture timing controller which controls timing of capture of the image by said camera;

a detector which detects an area projected on said screen;

an image size controller which changes, based on detection results from said detector, the captured image from said camera into a predetermined image size; and

an extractor which comprises a comparator which compares a signal of said captured image the size of which is changed by said image size controller with an image signal controlled by said display device controller and extracts a person area in said captured image;

wherein;

said display device controller controls said picture display device so that an area of an image produced on said image display device corresponding to the extracted person area is modified in accordance with predetermined data, and

said display device controller controls said picture display device based on the image signal input to said display device controller, at least during a period when said camera captures an image projected onto said screen.

6. A projector type display apparatus according to claim 5, wherein said predetermined data is either particular uniform color data, black data or image data having a low intensity level, superimposed on said image signal input to said display device controller.

7. A projector type display apparatus according to claim 5, wherein said extractor further comprises a motion detector which detects a motion area from the captured image data out of the projected area.

8. A projector type display apparatus according to claim 5, wherein said capture timing controller is configured to determine a capture interval and a capture exposure time based on cumulative light intensity for a predetermined time period.