They indicate the exposure either with a needle galvanometer or on an LCD screen.
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A type of galvanometer that permanently recorded measurements was the chart recorder.
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Most modern uses for the galvanometer mechanism are in positioning and control systems.
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Beginning in 1901, Einthoven completed a series of prototypes of a string galvanometer.
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This is despite the use of a highly sensitive mirror galvanometer, a new invention of the time.
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It reflects off of a curved mirror onto a galvanometer-mounted mirror which provides the vertical refresh.
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A tangent galvanometer is an early measuring instrument used for the measurement of electric current.
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A tangent galvanometer consists of a coil of insulated copper wire wound on a circular non-magnetic frame.
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In this case, the galvanometer need not be especially strong.
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More examples
Meter for detecting or comparing or measuring small electric currents
A galvanometer is a type of ammeter: an instrument for detecting and measuring electric current. It is an analog electromechanical transducer that produces a rotary deflection of some type of pointer in response to electric current flowing through its coil. ...
A device used to indicate the presence and direction of a small electric current, especially used to detect a null or balanced condition in a bridge circuit
A device for showing the presence and measuring the quantity of electricity. When an electrical current is passed through the coil of a galvanometer, a magnetic needle near the coil is deflected. This can be calibrated to provide a measure of the quantity of electricity. ...
An instrument designed to detect and indicate the magnitude of small currents.
A very high precision motor with a limited axis of rotation. Used to turn mirrors and guide laser beam. Referred to as "galvos."
A scientific instrument used in marketing research to measure the reaction of a subject in a study to an advertisement; the instrument measures the perspiration that accompanies the subject's interest or arousal. See Galvanic Skin Response.
A type of stepper motor of sorts, typically called a scanner, that spins a small shaft that a mirror is mounted on. ...
A galvanometer is used when we want to detect very weak current in an electric current or to know the direction of flow of current in a circuit.