Abstract: An optical signal data transceiver comprises a convex mirror to direct received optical signals onto at least one detector responsive to corresponding optical wavelengths. At least one optical emitter is arranged to irradiate the convex mirror such that the emitted optical radiation is reflected from the convex mirror in a diffuse manner. The specific shape of the convex mirror is selected to obtain a desired transmission and reception specificity and suitable shapes include, as non limiting examples, segments of spheres, hemispheres, paraboloids of revolution, right cones, etc.

Abstract: The present invention provides means for sequencing various supply voltages to electronic circuits and devices to thereby protect those circuits and devices from exposure to deleterious voltages. A first transistor switch connects a first voltage source to a first output terminal. A second transistor switch is connected to the control electrode of the first transistor switch. The second transistor switch, when conducting, causes the first transistor switch to conduct. The second transistor switch is turned on by a second voltage source which is connected through a delay circuit to the control electrode of the second transistor switch. The second voltage source also is connected through a diode and capacitor circuit to a second output terminal.