Abstract: Multiple stage ranging circuitry for a measuring circuit includes a first ranging circuit that selectively amplifies an input signal by respective amounts according to the magnitude of the input signal thereto, and a second ranging circuit coupled to the output of the first ranging circuit selectively amplifies the output signal from the first ranging circuit by a respective amount according to the magnitude of that output signal to provide a measured output. The multiple stage ranging circuitry increases dynamic range and provides for high speed measurements over that dynamic range.

Abstract: An miniature integrating sphere has a spherical volume with walls of a material for reflecting light, a light inlet and a light outlet. The light inlet is offset from a diameter axis of the spherical volume and the light inlet and light outlet are offset at non-perpendicular and non-parallel relation to each other. The light inlet is molded or milled to a shape conforming to the shape of the cone of light provided by a fiber optic device as an input to the integrating sphere. A number of miniature integrating spheres may be used respectively in plural channels of an optical measurement instrument.

Abstract: A range selection circuit (13), including a logarithmic amplifier (23) and output circuitry (25) associated therewith, is configured to directly drive linear ranging circuitry for measurement circuitry (12) in an optical power meter (10) to measure signals that vary over a wide range of, for example, from about −7 dB to about −45 dB. This allows the optical power meter to change ranges as fast as one (1) times the hardware settling time. The range selection circuitry is in parallel with the measurement circuitry, which allows ranging to happen in real time.