Light control system

• US 4,095,139 A
• Filed: 05/18/1977
• Issued: 06/13/1978
• Est. Priority Date: 05/18/1977
• Status: Expired due to Term

• Current Assignee: Vari-Lite, Inc. (Signify N.V.)
• Original Assignee: Alan P. Symonds, William K. Durfee
• Inventors: Durfee, William K., Symonds, Alan P.
• Primary Examiner(s): Smith, Alfred E.
• Assistant Examiner(s): Roberts, Charles F.
• Application Number:
  US05/798,259
• Time in Patent Office: 391 Days
• Field of Search: 315/154, 315/153, 315/158, 315/159, 315/291, 315/293, 315/294, 315/314, 315/315, 315/316
• US Class Current: 315/153
• CPC Class Codes: H05B 47/155 Coordinated control of two or more light sources

Abstract

A light control system for selectively controlling the light intensity levels of a plurality of light groups, each group including one or more lights, is disclosed. The system comprises a control for generating a parallel binary-coded signal representative of a predetermined current level to be applied to a particular light group; a signal generator for providing (1) a unique and predetermined serially-coded address signal corresponding to the particular light group and, (2) a serially-coded data signal representative of the current level in response to the parallel binary-coded signal, and; a plurality of receivers, at least one for each light group for applying the current level to the particular light group only in response to the address signal and data signal. A common wire bus for transmitting the address and data signals from the signal generator to each of the receivers is utilized to substantially reduce the wiring required.

Claims

1. A system for controlling the light intensity level of a light group including one or more lights, said system comprising, in combination:

control means for generating a parallel binary-coded signal representative of a predetermined signal level to be applied to said light group;

signal generating means for generating a unique and predetermined serially-coded address signal corresponding to said light group and for generating a serially-coded data signal representative of said signal level in response to said parallel binary-coded signal;

receiver means for applying said signal level to said light group only in response to said address signal and said data signal; and

a common bus for transmitting said address and data signals from said signal generating means to said receiver means.

2. A system in accordance with claim 1, wherein said control means includes switching means movable between a first position wherein said parallel binary-coded signal is representative of a preselected minimum signal level and a second position wherein said parallel binary-coded signal is representative of a preselected maximum signal level.

3. A system in accordance with claim 2 wherein said control means including a plurality of said switching means, said plurality of switching means being connected to said signal generating means by a common control bus, wherein each of said plurality of switching means generates a parallel binary-coded signal to said signal generating means on said common bus.

4. A system in accordance with claim 2 wherein said switching means includes a photomask having a plurality of tracks, and means including an array of photosensitive elements disposed on one side of said photomask and movable between said first and second positions so that said photosensitive elements can be selectively energized depending upon the position of said elements relative to said tracks of said photomask.

5. A system in accordance with claim 2 wherein said generating means generates as a pair each address signal with the data signal to be applied to the receiver means responsive to the address signal of said pair.

6. A system in accordance with claim 5 further comprising a plurality of said switching means, each for generating a parallel binary-coded signal representative of a predetermined signal level to be applied to a different one of said light groups, and a plurality of said receiver means, each of said receiver means being responsive to a predetermined address signal, wherein said signal generating means generates a different address signal and a data signal representative of the signal level of the parallel binary-coded signal for each of said switching means.

7. A system in accordance with claim 4 wherein said receiver means comprises latch means for holding a data signal;

means responsive to the data signal held by said holding means, for applying said signal level to said light group;

address means for comparing each address signal, generated by said signal generating means and transmitted over said common bus, with the unique and predetermined address to which said receiver means is responsive and for generating an enabling signal only when the address signal transmitted is the same as said unique and predetermined address;

wherein said latch means is responsive to said enabling signal for holding the data signal accompanying said address signal when said address signal is the same as said unique and predetermined address.

8. A system in accordance with claim 7 wherein said signal generating means further comprises memory means for storing signals, each representative of a signal level to be applied to a particular light group.

9. A system in accordance with claim 8 wherein said plurality of switching means includes master switching means for proportionately increasing or decreasing all the signal levels applied to each of said light groups.

10. A system in accordance with claim 8 wherein said signal generating means further comprises at least two registers, each for holding a plurality of said store signal, each representative of a signal level to be applied to a different light group, means for transferring said signals between said registers and said memory means.

11. A system in accordance with claim 10 wherein said plurality of switching means includes at least two master switching means, each for proportionally increasing or decreasing all of the signal levels applied to each of said light groups as determined by said store signals in a corresponding one of said registers.

12. In a light control system for generating a parallel binary-coded signal representative of a light intensity signal level to be applied to a light group of one or more lights, an improved switching device comprising in combination:

manually adjustable means movable between a first position, wherein said parallel binary-coded signal is representative of a preselected minimum light intensity signal level and a second position wherein said parallel binary-coded signal is representative of a preselected maximum level;

a Gray-coded photomask having a plurality of tracks;

means including an array of photosensitive elements corresponding to the number of tracks of said photomask disposed on one side of said photomask and movable with said manually adjustable means between said first and second positions so that said photosensitive elements are capable of being selectively energized to produce a parallel gray-coded output signal the values of which depend upon the position of said elements relative to said tracks of said photomask; and

means for converting said parallel Gray-coded output signal into said parallel binary-coded signal.

13. In a light control system including means for generating a serial binary-coded signal including a first portion representative of a light intensity signal level to be applied to a predetermined light group of one or more lights and a second portion representative of said predetermined light group, an improved device comprising:

register means for receiving said serial binary-coded signal one bit at a time and for converting the part of said serial binary-coded signal in said register to a corresponding parallel binary-coded signal;

clocking means for clocking said first and second portions of said signal into said register means;

means for encoding said device with a predetermined binary-coded address;

comparator means for comparing said second portion of said signal with said predetermined binary-coded address when said second portion of said signal is present in said register means and for generating a first enable signal only when the binary-coded sequence of said second portion matches said predetermined binary-coded address;

means responsive to said first enable signal for generating a second signal when said first portion of said signal is present in said register means;

converter means for converting said first portion of said signal to an analog signal substantially equal to the light intensity signal level represented by said first portion; and

gating means responsive to said second enable signal for transmitting said first portion of said signal to said converter means.

14. A system for controlling the light intensity level of a light group including one or more lights, said system comprising, in combination:

control means for generating a parallel binary-coded signal representative of a predetermined signal level to be applied to said light group, said control means including manually adjustable means movable between a first position, wherein said parallel binary-coded signal is representative of a preselected minimum light intensity signal level and a second position wherein said parallel binary-coded signal is representative of a preselected maximum level; and

a photomask having a plurality of tracks, means including an array of photosensitive elements corresponding to the number of tracks of said photomask disposed on one side of said photomask and movable with said manually adjustable means between said first and second positions so that said photosensitive elements are capable of being selectively energized to produce a coded output signal, the values of which depend on the position of said photosensitive elements relative to said tracks of said photomask; and

means for converting said coded output signal into said parallel binary-coded signal;

signal generating means for generating a unique and predetermined serial-coded address signal corresponding to said light group and generating a serially-coded data signal representative of said signal level in response to said parallel binary-coded signal;

receiver means for applying said signal level to said light group only in response to said address signal and said data signal, said receiver means including register means for receiving said address and data signals from said signal generating means one bit at a time and for converting each of said signals to parallel binary-coded form, clocking means for clocking said address and data signals into said register means, means for encoding said receiver means with a predetermined binary-coded address, comparator means for comparing said address signal with said predetermined address when said address signal is present in said register means and for generating a first enable signal only when the binary-coded sequence of said addresss signal matches said address, means for generating a second enable signal only in response to said first enable signal when said data signal is present in said register converter means for converting said data signal to an analog signal substantially equal to the light intensity level represented by said data signal, and gating means responsive to said second enable signal for transmitting said data signal to said converter means; and

a common bus for transmitting said address and data signals from said signal generating means to said receiver means.

15. A method of controlling the light intensity level of a light group including one or more lights, said method comprising the steps of:

generating a parallel binary-coded signal representative of a predetermined signal level to be applied to said light group;

generating a unique and predetermined serially-coded address signal corresponding to said light group and a serially-coded data signal representative of said signal level in response to said parallel binary-coded signal;

transmitting said address and data signals from said signal generating means to said light group over a common bus; and

applying said signal level to said light group only in response to said address signal and said data signal.