The 3nethra auto refractometer is portable device which is built with the latest Wave front sensing technology to ensure fast and accurate refractive measurement of the human eye which can be translated into a prescription for the glasses.Designed and developed with “SHACK HARTMANN” techniqueProduct Specifications :Usage/Application : Eye ExaminationModel Name/Number : AberroTypes Of Refractometer : DigitalMeasurement Mode : Refractometry ModeData Output Options : Built in PrinterWeight : 650gm.Power Supply : 5V DC Micro USB ADisplay Size : 3.5" Color touch screen / USB and BluetoothAxis Angle : 0 to 180 degrees,1-degree incrementVertex Distance : 12mmTechnical Specifications :Spherical measurement range : -14D to +14D, increments (0.25D)Cylindrical measurement range : -7D to 0D, increments (0.25D)Axis measurement range : 0 to 180 degrees, with 1-degree incrementMinimum pupil diameter : 2.5 mmVertex distance : 19.5 mmPatient age range : Above 5 yearsInternal fixation : Low spatial frequency sinusoidal grating with Gaussian envelopeBattery life : 8 hours with normal usage when fully chargedDisplay / connectivity : 3.5” color touch screen / USB and BluetoothTechnology : Wave-front sensingPower source : AC 100 to 240 V, 50 / 60 HzMeasurement time : <5 seconds per eyeWeight / dimension : 650 g / 8.9” X 7.2” X 2.9”Total weight : 11.1 kgs (3.4 kgs tricam + 7.7 kgs stand)Internal storage memory : 300 measurementsWorking environment light : Ambient lightCalibration : Not requiredBattery pack : Lithium-ion battery 3.6V, 6800 mAhAdditional feature : Telemedicine compatibleOptional accessories : Bluetooth printer, portable standStandard accessories : Suitcase, device charger 3nethra Handheld Auto Refractometer