Eye protection system wherein a low power laser controls a high power laser

• US 5,837,996 A
• Filed: 07/02/1997
• Issued: 11/17/1998
• Est. Priority Date: 12/02/1994
• Status: Expired due to Fees

• Current Assignee: Eytan Keydar
• Original Assignee: Eytan Keydar
• Inventors: Keydar, Eytan
• Primary Examiner(s): Westin, Edward P.
• Assistant Examiner(s): PYO, KEVIN K
• Application Number:
  US08/887,146
• Time in Patent Office: 503 Days
• Field of Search: 250/221, 250/205, 372/38, 372/25
• US Class Current: 250/221
• CPC Class Codes: A61F 9/022 Use of special optical filters, e.g. multiple layers, filters for protection against laser light or light from nuclear explosions, screens with different filter properties on different parts of the screen; Rotating slit-discs optical filters per se G02B5/20

Abstract

A system for preventing damage to the eyes of a person being within a certain distance from a high-power laser, including a device for ascertaining the absence of a person within this range, and a device for actuating the high power laser only if the results indicate that no such person is present in the specified range. There is also provided a method for eye protection against damage by high-output lasers, which comprises examining such a range with a low power laser or other similar device, harmless to a person'"'"'s eyes within the specific range, and for actuating high power laser radiation only after a clear indication that no person is present within the dangerous range.

Claims

1. An eye-safe laser comprising proximity range-measurement sensing means utilizing a low power light source for ascertaining whether a person is present up to the range at which the laser beam will cause eye damage, and means for actuating a high power laser only if no person is present within such a range.

2. A system according to claim 1, which comprises a proximity range-measurement means for actuating the laser at a reduced power output and means for establishing the presence or absence of a person within the range where full laser power will cause eye damage, and depending on the results of this test, means for actuating the full power laser only if no person is within the dangerous range.

3. A system according to claim 1, comprising a subsystem with a low-power output laser, means for using its low power beam for range-measuring to ascertain the presence or absence of a person in the range where eye damage will be caused by the high-power laser, and means for directing said low-power beam in the direction of a target though an optical system for the high-power laser.

4. A system according to claim 3, where the low-power laser beam source is a laser diode.

5. A system according to claim 3, where the low-power output laser is a laser operated at a pulse mode or in a continuous mode.

6. A system according to claim 1, comprising an auxiliary laser of weak power and means to operate it in a mode of operation different from that of the high power laser.

7. A system according to claim 1, comprising means for remote sensing using microwaves, millimeter waves or acoustic waves.

8. A system according to claim 1, incorporated in a range finding or target designating device.

9. A method for protecting a person against damage by laser radiation, which comprises examining a range up to which a high power laser is likely to cause eye damage to the eyes of a person, said examination being effected by proximity range-measurement detecting means utilizing a low power light source selected from a low power laser beam, microwaves, millimeter waves and acoustic waves, and according to the determination that no person is within said range, actuating a high power laser.

10. A method according to claim 9, where a high-power laser is actuated at such reduced power so as not to cause eye damage to a person within a certain range, and after ascertaining that no person is present within said range, actuating said high-power laser at full power.

11. A method according to claim 9, where the low power laser beam is produced by a laser diode.

12. A method according to claim 9, which comprises operating the low-power laser in a pulse mode or in a continuous one, or in a mode of operation different from the mode of operation of the high-power laser.