Catalogue Number: 555 Streak retinoscope head, self luminous Category: Equipment Sub-Category: Retinoscope Time Period: 1940 to 1999 Place Of Publication/Manufacture: Long Island, New York Publisher/Manufacturer: National Electric Instrument Company Incorporated Description Of Item: Black plastic body for a light source and mirror to deflect the light into the patient's eye with symbols and letters engraved in white on the patient side of the instrument for patient fixation during dynamic retinoscopy. On the examiner's side is a circular degree scale marked out in white engraved numerals with a ball bearing contained in a circular groove as the index of the angular rotation of the instrument. White lines mark the 90 position. A screw neck connects the head to a battery handle.The National Electric Instrument Company was granted Patent US2331591 for this retinoscope on October 12, 1943. Historical Significance: Most streak retinoscopes rotate the slit to locate the axis of astimatism. This retinoscope is unusual in that the examiner rotates the whole instrument. Streak retinoscopy was noted by Jackson in 1896 and advocated by Wolffe 1900-17. Dynamic retinoscopy was introduced by Cross (1903-1911) and popularised in the USA by Sheard (1922). It measures refraction when the eyes are actively accommodated and converged. How Acquired: Donated by Alan Isaacs, honorary life member of the College Date Acquired: Jan 2008 Condition: Good Location: Archive room. West wall. Unit 6 Drawer 4 |