FULYEE Optical Digital Pupilometer Pd Meters LCD Display Optical Pd Meter Digital Pupilometer Pupillary Distance 45-82mm Pupil Meter

ACCURACY MEASURE PUPILLARY: PD Meter is a precision optical instrument used to measure distance between pupils in the process of optometry for spectacles.

It features direct point-sampling and high accuracy of orientation.

TURN OFF AUTOMATICALLY: Turns off after 1 minute or you can press a button and shut it off.

It stays on and drains the batteries.

Store device flat side down, it will turn off automatically.

LED LAMP-HOUSE AND LOW POWER-CONSUMPTION DESIGN: The Design of LED Lamp-House and Low Power-Consumption Makes the Battery Life Prolonged.

The Brightness of LED Is Adjustable.

+2.0d Compensation for The Degree of Eyesight Is Available.

LONG READING TIME-It does retain the readings on screen while it is on and even in memory when it is switched back on as long as the slide controls have not been moved.The didital PD Meter does have a reading which lasts approximately 10 minutes CAUTIONS: If a pupilometer is not used, the center of the lens may be in the wrong spot, and will cause the person to be unable to see; glasses may be fit poorly and cause physical discomfort, eye strain and fatigue, and headaches.