Off-axis light-detector assembly

• US 20030106991A1
• Filed: 08/02/2002
• Published: 06/12/2003
• Est. Priority Date: 12/07/1999
• Status: Abandoned Application

• Current Assignee: Hagai Sigalov, Moshe Klotz
• Original Assignee: Hagai Sigalov, Moshe Klotz
• Inventors: Klotz, Moshe, Sigalov, Hagai
• Application Number:
  US10/149,070
• Publication Number:
  US 20030106991A1
• Time in Patent Office: Days
• US Class Current: 250/221
• CPC Class Codes: G10H 1/00 Details of electrophonic musical instruments
• CPC Class Codes: G10H 1/0553 using optical or light-responsive means
• CPC Class Codes: G10H 2220/411 Light beams
• CPC Class Codes: G10H 2240/311 MIDI transmission G10H2240/056 takes precedence

Abstract

A light-detector assembly is provided for use with light-actuated, selectively operable, electronic triggering equipment for triggering a wide variety of different kinds of events, particularly performance, entertainment, advertising or information events. Said assembly comprises light-detecting means (19; 53; 80); means for locating said light-detecting means off-axis in relation to a collimated source of visible light (L; 40), light deflecting means (18; 52; 78); and positioning means (14: 46; 74) for positioning said light-detecting means on the optical axis of said collimated source; wherein said deflecting means are adapted to deflect towards said light detecting means, light, such as retro-reflected light, that is directed towards the source. Said deflecting means may comprise a mirror (19, 53, 76) adapted to reflect said light to the light detector, and in some embodiments the deflecting means (78) may comprise a plurality of mirrors (76) and a corresponding plurality of light-detectors (80) may be provided that are spaced around the beam, wherein each of the light-detectors is collimated with a respective one of the mirrors.

Claims

1. A light-detector assembly for use with light-actuated, selectively operable, electronic triggering equipment, which assembly comprises light-detecting means (20;

54;

80);

means for locating said light-detecting means off-axis in relation to a collimated source of visible light (L;

40);

light deflecting means (19;

53;

78); and

positioning means (14;

48;

74) for positioning said light deflecting means on the optical axis of said collimating source;

wherein said deflecting means are adapted to deflect towards said light-detecting means, light, such as retro-reflected light, that is directed towards the source.

2. A light-detector assembly as claimed in claim 1, wherein the detector (20;

54;

80) is adapted to detect light from the light source that is retroreflected back towards the source.

3. A light-detector assembly as claimed in claim 1 or claim 2, further comprising a mirror (M) that may be positioned at said point remote from said light source (L) in order to reflect further in a desired direction a beam emitted by said source (L).

4. A light-detector assembly as claimed in claim 3 wherein said mirror (M) is moveable to alter the direction of the further reflected beam.

5. The light-detector assembly as claimed in any preceding claim wherein said deflecting means comprise a mirror (19;

53;

76) adapted to reflect said light to the light-detector.

6. A light-detector as claimed in claim 5, wherein said mirror (19;

53;

76) is concave and adapted to focus the light onto the light-detector.

7. A light-detector assembly as claimed in claim 5 or claim 6, wherein said mirror comprises a conventional, substantially opaque mirror (19;

76) or a one-way mirror (53).

8. A light-detector assembly as claimed in claim 7, wherein the one-way mirror (53) is adapted to transmit light through the mirror in one direction and is wholly or substantially opaque to light in another direction.

9. A light-detector assembly as claimed in claim 8, wherein said one-way mirror (53) is positioned within a beam of light emitted by the light source (40) to allow the passage of light therethrough away from the source and to be opaque to light that is retro-reflected towards the source.

10. A light-detector assembly as claimed in claim 7, claim 8 or claim 9, wherein said one-way mirror (53) is mounted in the beam emitted by the light source (40) on a hollow support member (50).

11. A light-detector assembly as claimed in any preceding claim wherein said light-detector (20;

54;

80) comprises an elongate tube (24;

56;

84), open at one end (26;

58;

86), which accommodates a light-sensitive element (30;

60;

90).

12. A light-detector assembly as claimed in claim 11, wherein said tube (24;

56;

84) is positioned such that the light-sensitive element (30;

60;

90) is collimated with a retro-reflected beam.

13. A light-detector assembly as claimed in claim 11 or claim 12, wherein said tube (56;

84) is oriented substantially parallel to the beam and comprises a further mirror (62;

92) adapted to further reflect light deflected by the deflecting means (52;

78) in to the open end of the tube (58;

86) on to the light-sensitive element (60;

90).

14. A light-detector assembly as claimed in claim 11, claim 12 or claim 13, wherein the open end (58;

86) of the tube (56;

84) is directed away from the light source (40;

L).

15. A light-detector assembly as claimed in any preceding claim which forms part of an integrated light unit (40) comprising a light source (42) and means (44, 46) for collimating light from said light source to form a parallel beam.

16. A light detector assembly as claimed in claim 15, wherein said deflecting means (50) are mounted on a lens (46) adapted for collimating light from the light source.

17. A light detector assembly as claimed in any of claims 1 to 14, wherein said light-detector assembly is adapted to be retrofitted to an existing light unit (L) comprising a light source.

18. A light-detector assembly as claimed in claim 17, wherein the deflecting means (18;

76) are mounted on a spider (14;

74) which is adapted to be fixedly secured to the light unit (L) within the beam.

19. A light-detector assembly as claimed in any preceding claim wherein said deflecting means (76) comprise a plurality of mirrors (78), and a corresponding plurality of light-detectors (80) are provided that are spaced around the beam, wherein each of said light-detectors is collimated with the respective one of the mirrors.

20. A light-detector assembly as claimed in claim 19, wherein each light-detector (80) is “

tuned”

to detect light of the same or different wavelength from the other light detectors.

21. A light-detector assembly as claimed in claim 19 or claim 20 wherein said deflecting means comprise a pyramid (76) having a plurality of mirrored faces (78).

22. A light-detector assembly as claimed in claim 21, wherein said pyramid comprises 3, 4, 5 or more faces (78).

23. A light-detector assembly as claimed in any of claims 19 to 22 wherein said mirrors (78) are contiguous or spaced from one another across the axis of the beam and a plurality of light detectors (80), each associated with the respective one of the mirrors, are used to detect the speed with which and/or the direction from which the beam is cut.

24. A light-detector assembly as claimed in any of claims 19 to 22, wherein said detectors (80) are used to drive a plurality of different, triggerable devices.

25. A light-detector assembly as claimed in any of claims 19 to 24, wherein one of said light-detectors (80) is adapted to detect non-visible light (eg infra-red light), and another of said light detectors is adapted to detect visible light, and comparing means are provided for generating an output trigger signal only when a qualitative change in the intensity of light is detected by both said non-visible light detector and said visible light detector.

26. A light-detector assembly as claimed in any of claims 19 to 24, further comprising a plurality of pieces of different kinds of retro-reflective material, wherein each kind of retro-reflective material is adapted to retroreflect exclusively light of a specific wavelength or a range of wavelengths corresponding to a respective one of the light-detectors (80);

said pieces being fixed remotely in relation to the light-detector assembly and spatially arranged in non-overlapping relation to each other; and

each mirror (78) being oriented to receive retro-reflected light from a respective one of said pieces.

27. A light-detector assembly as claimed in any preceding claim wherein the or each light-detector (20;

54;

80) incorporates a pulse generator for converting the output analogue signal of the light-sensitive element (30;

60;

90) to a digital trigger signal.

28. A light-detector assembly as claimed in any preceding claim further comprising a tiltable mirror (M) spaced from the deflecting means (76) on the optical axis of the beam;

which tiltable mirror is adapted to be tilted to adjust the direction of the beam.

29. A light-detector assembly as claimed in claim 28, wherein movement of the tiltable mirror is motorised and optionally computer-controlled.