GB1464565A - Light source measuring apparatus - Google Patents

Abstract

1464565 Light source measuring apparatus XEROX CORP 28 Oct 1974 [29 Oct 1973] 46497/74 Heading G1A Apparatus for testing an elongated apertured tubular light source 24 comprises photo-cell 18 for measuring the source output in a given direction, a filter on frame 44 interposable between source 24 and photo-cell 18 and means 26, 28 for mounting source 24 horizontally with its longitudinal axis perpendicular to said direction and allowing its aperture to be rotatably aligned with collimator 40 between filter 42 in position and photo-cell 18. The analogue signal is converted to digital. On bar 30, which is secured moveably to frame 32 and has indicator marks, are slideably mounted brackets 26 and 28 having rotatable lamp sockets. Four filters 42 are held by retaining rings on disc 44, bearing five magnets, four indicating filter positions and one a fifth position. A cover is mounted over wheel 20 and belt 46. Motor 22 makes 200 steps per revolution. Depressing button 48 allows disc 44 to rotate to the fifth position, detected by magnetic relay 50, and sets flip-flop 52, which through AND gates 11 and 13 gates step pulses from 180Hz oscillator 66 to translator module 54 and which is disabled by signal SW2, which also via delay logic 31 and invertor 33 advances the printer paper. Signal SW1 clears mode counter 56 and character counter 58. On switching the RUN switch, the AUTO signal triggers a single shot timer 60 through NAND gate 15 and uni-junction timer 62. Signal SSD from NAND gate 17 sets run flip-flop 64 to activate the FILAMENT ON signal and the lamp, and a-constant current linear reactor is powered as the signal from timer 60 finishes and RUN is actuated gating step pulses to module 54, so that disc 44 rotates until the correct filter position, which has been determined by switching mode counter 56, is detected by magnetic relay 68, which triggers single shot timer 72 disabling the step pulses for 500ms while a reading is taken followed by a PRINT COMMAND signal an INHIBIT signal and a HOLD signal to maintain digital display. Relay 68 also toggles character counter 58 giving binary coded signals for red, green, blue and cyan gated through register 35 to switch on a POT channel on the printer. Thus at the end of 500ms, the printer prints the reading and the filter character. The above procedure is repeated for each filter position. The process ends when relay 50 of the fifth position causes shut down.