PI-381 Perimeter Priestley Smith Model
The perimeter is an instrument for the accurate charting of the field of vision. It consists of a vertical stand on witch a metallic arc is pivoted. It also bears a circular black disc to read the meridian in which the arc in shape of a semicircle with radius 330mm. It’s rotating in any direction and fix at any position with a tightening screw. The arc is graduated from 0º to 90º with a movable test object which is a white color spot of size 10mm diameter painted on a circular disc it can be moved with the arc. An adjustable chin rest and a detachable leveling bar is fixed in front of the metallic arc. A Scale and circular chart frame to hold the chart paper in position are provided at the back of the circular disc. A metallic graduated scale with a movable Pin-Punch pointer is fixed to mark on the perimeter chart paper. Supplied With 100 charts.
PI-382 Perimeter (Lister Type)
Automatically records field to 90° in all meridians. The Carrier mechanism is smooth, silent and invisible. The patient perceives only the test object to move. Spring check, giving an Audible click to each 15° of rotation of the arc in either direction Renders close scrutiny of dial plate unnecessary and ensures accurate registration. The device can be thrown out of action if the silent movement is desired The marker a needle is housed in a retractable tube, sprung to Sheath the pint when not actually marking. A set of interchangeable and permanent washable test objects is included with the instrument. The objects subtend angles of 4°, 2°, 1 °, ½°, ¼° and are in white, green and red-blue objects in the last three sizes are also included. Supplies complete with Transformer to work on 220 Volt A/C mains With 100 charts.