Reflective Mirror Galvanometer

Quick Answer: The Reflective Mirror Galvanometer is a sensitive current-detecting instrument that uses a small mirror mounted on its moving system, together with a light beam and scale, to convert a tiny mirror rotation into a large, clearly visible movement of a reflected light spot.

Product Description

The Reflective Mirror Galvanometer from LabEquip is built for laboratory demonstrations in which a very small mechanical deflection needs to be observed at a greatly enlarged scale. Inside a conventional moving-coil or moving-magnet galvanometer, current passing through the coil produces a small torque that rotates the moving system against a restoring spring or suspension. In a reflective (optical-lever) design, a small mirror is fixed to this moving system in place of, or alongside, a mechanical pointer.

A light beam is directed at the mirror and reflected onto a separate scale or screen placed some distance away. Because the reflected beam sweeps through twice the angle of the mirror’s own rotation, and because the light path itself acts as a long, weightless “pointer,” even a very small current can produce a visible spot movement that a mechanical needle could never show at the same sensitivity. This optical-lever principle is the genuine basis of the classical mirror galvanometer used historically in sensitive current and voltage detection work, and it remains a valuable teaching demonstration of the relationship between current, magnetic torque and angular displacement.

The direction of deflection corresponds to the direction of current flow when the instrument is correctly connected, and the scale allows comparison of the light spot’s position against a central zero reference. Because this instrument is intrinsically a precision item, its exact current sensitivity, coil resistance and scale distance can vary by unit; these details should be confirmed with our sales team for the specific instrument supplied.

• Optical-lever amplification: converts a small mirror rotation into a much larger movement on a distant scale.
• Direction indication: deflection direction represents current direction when correctly connected.
• Zero-reference observation: supports comparison of the deflected spot against a central or established reference point.
• Advanced conceptual demonstration: links electric current, magnetic torque and angular displacement in one visible experiment.
• Reusable laboratory format: suited to demonstrations and supervised advanced physics practicals.
• Precision build: a more delicate, higher-value instrument than a standard classroom galvanometer.

Specifications

Care & Maintenance

• Handle the mirror surface with extreme care; avoid touching it directly, and clean only with the method recommended by our sales/support team for this instrument.
• Keep the instrument on a stable, vibration-free surface during use, since the optical lever is highly sensitive to physical disturbance.
• Avoid exposing the instrument to strong external magnetic fields, which can affect the moving system’s accuracy.
• Do not pass current through the instrument beyond the level appropriate for its sensitivity; confirm safe limits with our sales team before use.
• Store in a dry, dust-free enclosure when not in use to protect the mirror and suspension.
• Recheck the zero position and light-spot alignment before each demonstration session.

Why Choose LabEquip

LabEquip supplies laboratory measuring instruments for schools, colleges and technical training institutes, with honest documentation of what each instrument does and where its specifications must be confirmed directly. If you need a simpler current-presence indicator for introductory classes, see our Electrical Current Detection Device. For a calibrated moving-coil panel meter, see our Analog Moving Coil Instrument MR66, and for resistance measurement in a related bridge-style setup, see our Analog Ohmic Measurement Device.

Frequently Asked Questions

What does a reflective mirror galvanometer measure?
It detects and indicates very small electric currents by converting a tiny rotation of an internal mirror into a much larger, clearly visible movement of a reflected light spot on a scale.

How does the mirror amplify such a small movement?
The reflected light beam sweeps through twice the angle of the mirror’s own rotation, and the long light path acts like a weightless pointer, so even a very small current produces a visible spot movement that a mechanical needle at the same sensitivity could not show as clearly.

Does the direction of deflection mean anything?
Yes, when the instrument is correctly connected, the direction the light spot moves corresponds to the direction of current flow through the coil.

What is the exact current sensitivity of this instrument?
This can vary by unit. Please confirm the exact sensitivity and coil resistance with our sales team before ordering if this is critical for your application.

Is this suitable for a school-level physics class?
It is better suited to advanced or supervised physics laboratory demonstrations, given its precision and sensitivity, rather than routine introductory classroom use.

How do I get current pricing and confirm specifications?
Email [email protected] with your requirement, and our team will confirm current pricing, availability and technical specifications.

Last Updated: September 2026