The measurement system comprises a holder for holding a dielectric film formed on at least a semiconductive substrate and sandwiched between the substrate and a conductive film, voltage application terminals for applying voltage between the substrate and the conductive film, variable voltage source for supplying the voltage to the voltage application terminals, a light source for irradiating the dielectric film with light including wavelength of an infrared region and transmitting the light thro...

In the measurement system for the measurement of an object (2), the object 2) is provided with two retro-reflectors (3, 4) disposed at a known spacing. A measuring device (1) exhibits a light source (5), a video camera (7, 8) and an arrangement (9) which carries out the measurement with reference to the two image points which are formed by the light reflected by the retroreflectors (3, 4). The light source (5) is preferably a flash light source, the flashes of which are synchronized by an arrang...

A measurement apparatus that measures a current consumed by an electronic device is provided. The measurement apparatus includes: a power supply output terminal connected to the electronic device; a power supply voltage output section that output a power supply voltage; a diode switch section having two diodes connected in parallel between the power supply output terminal and the power supply voltage output section so as to rectify in the direction opposed to each other that applies the current ...

A measurement system for providing an indication of a varying physical quantity represented by or converted to a variable frequency signal. Timing pulses are obtained marking the duration of a fixed number, or set, of cycles of the sampled signal and these timing pulses are employed to control the period of counting of cycles of a higher fixed and known frequency source. The counts of cycles thus obtained from the fixed frequency source provide a precise measurement of the average frequency of e...

A conventional interferometer has been modified so that amplitude and phase information contained in an interference pattern may be calculated from intensities read out by a television camera and phase shifts introduced by rotation of a quarter-wave plate. To operate the device, reference light at a first phase is interfered on the television camera with light from the object being tested. Such an object might be a lens. The camera samples the intensity of the interference pattern at an array of...

Apparatus for measuring an unknown area within a predetermined area, comprising: a pointer movable over the predetermined area by an operator to track the boundary of the unknown area; first and second means movable with the pointer to define co-ordinates for the pointer position within the predetermined area, the first such means generating first electrical signals at regularly spaced intervals along one co-ordinate axis to represent a graticule, and the second such means generating second elec...

The temperature within a body is measured by covering an area of the body surface with a layer of thermal insulation, measuring the temperature with two sensors located respectively at the insulation/body surface interface and at the opposite side of the insulating layer to indicate any temperature gradient along a path from within the body through the sensors, and applying heat over the insulating layer/sensor sandwich to annul any such gradient. This effectively exteriorises the desired deep b...

An apparatus for measuring small currents in which the current is applied to an integrator. The integrator output is applied to a slope detecting means, preferably differentiator and the integrator output is reduced at intervals to zero.

The frequency response of a microphone can be measured by feeding an acoustic spectrum generated from a pseudo-random bit sequence generator into the microphone and analysing the output using a Fourier analyser. The acoustic spectrum generator is portable and battery operated. A phase locked oscillator system is used to enable the output of a microphone under test to be analysed even after recording on magnetic tape. The device ensures that the sampling rate of the analogue to digital converter ...

Angles and angular displacements of ultrasonic beams are measured by using a probe to transmit the beam to a point on a surface, particularly the surface of material being subjected to non-destructive examination, from which the beam is reflected to a receiving probe which may or may not be the same device as the transmitting probe. The length of the path traversed by the beam is varied in accordance with a relationship determined as a function of the angular displacement of the beam from an axi...