Optical encoder using time domain and wavelength multiplexing

A light wavelength signal encoding apparatus, comprising:

• plural pulsed light source means, each providing primary light pulses, each having a different light source wavelength, each propagating on a corresponding one of a first plurality of input fiber optic lines, each of said sources pulsed at an associated selected real time pulse width interval;
• first combiner-splitter means, responsive to each of said primary light pulses for combining said first plurality of input fiber optic lines at an input to a first fiber optic junction and for splitting said first fiber optic junction at an output thereof into a second plurality of transmitter fiber optic lines, each of said second plurality of transmitter fiber optic lines having all of said primary light pulses propagating thereon at reduced intensity in a wavelength multiplexed stream of secondary light pulses;
• encoder means, including a transmitter portion, a positionable mask portion having a spatial code with light transmissive and opaque regions in an array of channels imprinted thereon, and a receiver portion;
• said transmitter portion being responsive to said wavelength multiplexed secondary light pulses for presenting each of said second plurality of transmitter fiber optic lines in a spatial array on one side of said mask, said transmitter having each of said second plurality of transmitter fiber optic lines aligned with one channel of said array of channels;
• said mask portion transmitting and blocking selected ones of said wavelength multiplexed secondary light pulse streams according to said spatial code and said mask's position;
• said receiver portion having a second plurality of receiver fiber optic lines arrayed in alignment with said second plurality of transmitter fiber optic lines, responsive to said transmitting and blocking of said selected ones of said wavelength multiplexed secondary light pulse streams for propagation thereof;
• time delay means, having a second plurality of time delay fiber optic lines, each responsive at input ends thereof to said transmitting and blocking of a selected one of said selected ones of said wavelength multiplexed secondary light pulse streams propagated on said receiver fiber optic lines, for delaying the propagation of each successive one of said wavelength multiplexed secondary pulse streams by successively longer time intervals, the difference time delay between succeeding lines being equal;
• second combiner-splitter means, responsive to each of said delayed streams of wavelength multiplexed secondary pulses on said second plurality of time delay fiber optic lines, for combining said time delay fiber optic lines at output ends thereof at an input to a second fiber optic junction thereby combining said delayed streams in a time multiplexed manner and for splitting said second fiber optic junction at an output thereof into a first plurality of output fiber optic lines, each of said first plurality of output fiber optic lines having all of said time and wavelength multiplexed secondary light pulse streams propagating thereon;
• plural filter means, each responsive to one of said streams of secondary light pulses propagating on an associated one of said plurality of fiber optic output lines, each filter transmitting only light having a wavelength corresponding to said light source wavelength of an associated pulsed light source;
• and
• plural filtered light receiver means, each associated with an associated one of said filter means, each responsive to said light trarsmitted by said associated filter, for providing in response to the presence and absence of a transmitted pulse in each successive real time pulse width interval, output signal manifestations of the position of said positionable mask.