Control of luminous flux when person approaches path of projection rays emitted from projector

• US 6,598,979 B2
• Filed: 10/29/2001
• Issued: 07/29/2003
• Est. Priority Date: 04/25/2000
• Status: Active Grant

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Yoneno, Kunio
• Primary Examiner(s): DOWLING, WILLIAM C
• Application Number:
  US09/959,531
• Publication Number:
  US 20020159039A1
• Time in Patent Office: 638 Days
• Field of Search: 353/28, 353/97, 353/122, 353/85, 348/586, 348/590, 348/607
• US Class Current: 353/122
• CPC Class Codes: G03B 21/006 using LCD's
• CPC Class Codes: H04N 5/58 in dependence upon ambient light
• CPC Class Codes: H04N 5/74 Projection arrangements for image reproduction, e.g. using eidophor

Abstract

A projector of the present invention includes: an electro-optic device that outputs rays modulated according to a given image signal, an image processing unit that transmits the image signal to the electro-optic device, and a luminous flux control device that controls an output luminous flux of projection rays, which are output from the electro-optic device and projected. The luminous flux control device has: a detector unit that detects a person who approaches a path of the projection rays; and a controller unit that controls the output luminous flux of the projection rays when the detector detects the approach of the person.

This arrangement controls the output luminous flux of the projection rays when a person approaches the path of the projection rays and the projection rays directly enter the field of view of the person, thus effectively relieving the unpleasantness due to the incidence of the projection rays.

Claims

1. A projector comprising:

an electro-optic device that outputs rays modulated according to a given image signal;

an image processing unit that transmits the image signal to said electro-optic device; and

a luminous flux control device that controls an output luminous flux of projection rays, which are output from said electro-optic device and projected,

said luminous flux control device including;

a detector unit that detects a person who enters a path of the projection rays, and

a controller unit that controls the output luminous flux of the projection rays when said detector detects the entering of the person,

said detector unitincluding;

a luminance detector having a light receiving unit that is disposed in a neighborhood of a projection lens, from which the projection rays are output, and receives reflected rays obtained by reflection of the projection rays, said luminance detector outputting a reflection luminance of the reflected rays received by said light receiving unit as a reflection luminance signal,

a reference luminance level generator that specifies a reference luminance based on a luminance signal level of an image signal corresponding to the projection rays, and outputs the specified reference luminance as a reference luminance signal, and

a luminance comparator that compares the reflection luminance signal with the reference luminance signal, and

said controller unit controlling the output luminous flux of the projection rays according to an output of said luminance comparator.

7. A projector in accordance with claim 1, wherein said luminous flux control device further including an information unit that, when said controller unit controls the output luminous flux of the projection rays, informs the person of the controlled output luminous flux of the projection rays with at least one of a light, a voice and a picture.

2. A projector comprising:

an electro-optic device that outputs rays modulated according to a given image signal;

an image processing unit that transmits the image signal to said electro-optic device; and

a luminous flux control device that controls an output luminous flux of projection rays, which are output from said electro-optic device and projected,

said luminous flux control device including;

a detector unit that detects a person who enters a path of the projection rays, and

a controller unit that controls the output luminous flux of the projection rays when said detector detects the entering of the person,

said image processing unit including;

a reference image signal generator that generates a reference image signal, which is used to output the projection rays corresponding to a preset luminance signal level, and transmits the reference image signal to said electro-optic device,

said detector unit including;

a luminance detector having a light receiving unit that is disposed in a neighborhood of a projection lens, from which the projection rays are output, and receives reflected rays obtained by reflection of the projection rays, said luminance detector outputting a reflection luminance of the reflected rays received by said light receiving unit as a reflection luminance signal,

a reference luminance level generator that registers, as a reference luminance signal, a reflection luminance output from said luminance detector when the projection rays corresponding to the preset luminance signal level are output in response to the reference image signal, and

a luminance comparator that compares the reflection luminance signal with the reference luminance signal,

said controller unit controlling the output luminous flux of the projection rays according to an output of said luminance comparator.

8. A projector in accordance with claim 2, wherein said luminous flux control device further including an information unit that, when said controller unit controls the output luminous flux of the projection rays, informs the person of the controlled output luminous flux of the projection rays with at least one of a light, a voice and a picture.

3. A projector comprising:

an electro-optic device that outputs rays modulated according to a given image signal;

an image processing unit that transmits the image signal to said electro-optic device; and

a luminous flux control device that controls an output luminous flux of projection rays, which are output from said electro-optic device and projected,

said luminous flux control device including;

a detector unit that detects a person who enters a path of the projection rays, and

a controller unit that controls the output luminous flux of the projection rays when said detector detects the entering of the person,

said detector unit including;

a luminance detector having an infrared emission unit and an infrared receiving unit that are disposed in a neighborhood of a projection lens, from which the projection rays are output, said infrared receiving unit of said luminance detector receiving reflected rays of infrared radiation emitted from said infrared emission unit, said luminance detector outputting a reflection luminance of the received reflected infrared rays as a reflection luminance signal, and

a luminance comparator that compares the reflection luminance signal with a preset reference luminance signal,

said controller unit controlling the output luminous flux of the projection rays according to an output of said luminance comparator.

9. A projector in accordance with claim 3, wherein said luminous flux control device further including an information unit that, when said controller unit controls the output luminous flux of the projection rays, informs the person of the controlled output luminous flux of the projection rays with at least one of a light, a voice and a picture.

4. A projector comprising:

an electro-optic device that outputs rays modulated according to a given image signal;

an image processing unit that transmits the image signal to said electro-optic device; and

a luminous flux control device that controls an output luminous flux of projection rays, which are output from said electro-optic device and projected,

said luminous flux control device including;

a detector unit that detects a person who enters a path of the projection rays, and

a controller unit that controls the output luminous flux of the projection rays when said detector detects the entering of the person,

said detector unit including;

an ultrasonic wave detector having an ultrasonic wave transmitter unit and an ultrasonic wave receiver unit that are disposed in a neighborhood of a projection lens, from which the projection rays are output, said ultrasonic wave receiver unit of said ultrasonic wave detector receiving a reflected wave of an ultrasonic wave transmitted from said ultrasonic wave transmitter unit, said ultrasonic wave detector measuring a strength of the received ultrasonic wave, and

an ultrasonic wave comparator that compares the measurement of the received ultrasonic wave strength with a preset reference received ultrasonic wave strength, said controller unit controlling the output luminous flux of the projection rays according to an output of said ultrasonic wave comparator.

10. A projector in accordance with claim 4, wherein said luminous flux control device further including an information unit that, when said controller unit controls the output luminous flux of the projection rays, informs the person of the controlled output luminous flux of the projection rays with at least one of a light, a voice and a picture.

5. A projector comprising:

an electro-optic device that outputs rays modulated according to a given image signal;

an image processing unit that transmits the image signal to said electro-optic device; and

a luminous flux control device that controls an output luminous flux of projection rays, which are output from said electro-optic device and projected,

said luminous flux control device including;

a detector unit that detects a person who enters a path of the projection rays, and

a controller unit that controls the output luminous flux of the projection rays when said detector detects the entering of the person,

said detector including;

an ultrasonic wave transmitter unit that is disposed in a neighborhood of a projection lens, from which the projection rays are output;

an ultrasonic wave receiver unit that is disposed in the neighborhood of the projection lens and receives a reflected wave of an ultrasonic wave transmitted from said ultrasonic wave transmitter unit,

a time measurement unit that continues measuring time between transmission of the ultrasonic wave from said ultrasonic wave transmitter unit and receipt of the ultrasonic wave by said ultrasonic wave receiver unit, and

a time comparator that compares the observed time by said time measurement unit with a preset reference time,

said controller unit controlling the output luminous flux of the projection rays according to an output of said time comparator.

11. A projector in accordance with claim 5, wherein said luminous flux control device further including an information unit that, when said controller unit controls the output luminous flux of the projection rays, informs the person of the controlled output luminous flux of the projection rays with at least one of a light, a voice and a picture.

6. A projector comprising:

an electro-optic device that outputs rays modulated according to a given image signal;

an image processing unit that transmits the image signal to said electro-optic device; and

a luminous flux control device that controls an output luminous flux of projection rays, which are output from said electro optic device and projected,

said luminous flux control device including;

a detector unit that detects a person who enters a path of the projection rays, and

a controller unit that controls the output luminous flux of the projection rays when said detector detects the entering of the person,

said luminous flux control device further including;

an information unit that, when said controller unit controls the output luminous flux of the projection rays, informs the person of the controlled output luminous flux of the projection rays with at least one of a voice and a picture.