Stage lighting control units

Claim 2

A lighting control apparatus for controlling dimmers in a plurality of channels, comprising: A. a digital lighting-cue memory means for recording a plurality of series of dimmer control signals, each such series constituting a lighting cue, B. manual control means responsive to a manual input for selecting any given location in the lighting-cue memory means by providing electrical output signals to the dimmers to cause the dimmers to produce a lighting effect corresponding to the lighting cue stored in that location, and C. digital computation means responsive to operation of said manual control means for digitally computing a succession of incremental electrical signals which act upon said electrical output signals to cause a value of the output signals to move over a period of time from their levels which existed before said manual input to the levels recalled from the memory location by the operation of the manual control means.

Claim 3

Apparatus according to claim 1, in which the digital computation means performs an initial computation identifying those channels in which said output signal value must change from an existing level to a different level required by the new cue and thereby compiles a ''''movement list'''' identifying these channels and the sense and magnitude of the necessary changes in value, the movement list being subsequently used to compute said succession of outputs.

Claim 4

Apparatus according to claim 2, in which the digital computation means defines said magnitude as a predetermined number of equal increments.

Claim 5

A lighting control apparatus for controlling dimmers in a plurality of channels, comprising: A. a digital lighting-cue memory means for recording a plurality of series of dimmer control signals, each such series constituting a lighting cue, B. manual control means responsive to a manual input for selecting any given location in the lighting-cue memory means by providing electrical output signals to the dimmers to produce a lighting effect corresponding to the lighting cue stored in that location, C. a manually operable control member for setting the desired speed of cross-fading from one cue to a following cue selected by said control means, D. a clock responsive to said control member to produce electrical pulses at a rate determined by the setting of said control member, E. a resettable counter connected to receive said electrical pulses from the clock, and F. digital computation means responsive to the operation of said manual control means for computing a list defining the sense of change of illumination in each channel and the magnitude of each of a number of predetermined equal increments into which the necessary change is divided, and also responsive to the counter to subsequently increase the value of said electrical output signals of the channels sequentially by adding a respective number of said increments equal in number to the count held in the counter, the counter being reset each time all channels have been so incremented.

Claim 6

A lighting control apparatus for controlling dimmers in a plurality of channels, comprising: A. a digital lighting-cue memory means for recording a plurality of series of dimmer control signals, each such series constituting a lighting cue, B. manual control means responsive to a manual input for selecting any given location in the lighting-cue memory means by providing electrical output signals to the dimmers to produce a lighting effect corresponding to the lighting cue stored in that location, C. a manually operable control member for setting the desired speed of cross-fading from one cue to a following cue selected by said control means, D. a clock responsive to said control member to produce electrical pulses at a rate determined by the setting of said control member, E. a resettable counter connected to receive said electrical pulses from the clock, and F. digital computation means responsive to the operation of said manual control means for computing a list defining the sense of change of illumination in each channel and the magnitude of each of a number of predetermined equal increments into which the necessary change is divided, and also responsive to the counter to subsequently increase the value of said electrical output signals of the channels sequentially by adding a respective number of said increments equal in number to the count held in the counter, the counter being reset each time all channels have been so incremented.

Claim 7

Apparatus according to claim 4, including further manually operable control means to provide signals representing desired levels of illumination of selected lighting channels as inputs to the lighting-cue memory means.

Claim 8

Apparatus according to claim 4, in which the clock comprises a resistor and capacitor arranged in series across a voltage source, a computer having one input connected to receive the voltage on the capacitor and its other input connected to receive a voltage determined by said control member, a monostablE circuit triggered by the comparator output changing sign, and means responsive to the output of the monostable circuit for discharging the capacitor.

Claim 9

Apparatus according to claim 6, in which the voltage determined by the control member is derived from the slider of a linear potentiometer, the potentiometer being connected across said voltage source and its slider being mechanically coupled to said control member.

Claim 10

Apparatus according to claim 6, in which said means for discharging the capacitor comprises a transistor whose emitter -collector path is connected in shunt across the capacitor and whose base is connected to receive the output of the monostable circuit.

Claim 11

Apparatus according to claim 4, in which the digital computation means includes a binary shift register for computing the magnitude of said increments by dividing the required change by a constant which is a power of 2.