An ophthalmic perimeter and an ophthalmic screening device, two related items. A mechanical hand‑held ophthalmic perimeter / visual‑field screener, used by eye specialists to measure a patient’s field of vision, dating to roughly 1930–1940. The instrument has rotating black discs with numbered scales and apertures and a brass target disc, plus a detachable ribbed handle and a fitted green‑velvet case. In use, the examiner held it in front of the patient’s eye and moved the brass disc or changed apertures while the patient fixated centrally, reading off the scales to record visual‑field limits or scotoma positions in different meridians.​ Good original condition. An ophthalmic screening device, used in optometry to analyse how the eyes work together (binocular function) rather than to look inside the eye. Each end is marked LEFT EYE / RIGHT EYE and carries a rotating disc with scales and a coloured or lined filter; the clinician looks through (or places it before the patient’s eye) and rotates the dial while the patient views a test target. By changing the orientation and type of filter (often red or striated lenses) and reading from the scale, the optometrist could measure heterophoria, fixation disparity or muscle imbalance—essentially how much the eyes want to drift when not forced to work together.​ The patient would look at a light or special test chart whilst the examiner holds this device in front of one or both eyes and rotates the dials, the patient would then report when certain lines, lights or images line up or cross; the examiner read the corresponding values from the scale to determine the degree and direction of imbalance. Black painted alloy body with significant paint loss, engraved white legends, acrylic (Perspex) discs and brass screws. Both items are offered as collectible/display items and are therefore untested.