Nidek ARK-700 Autorefractor-Keratometer: Optical Precision Serving Visual Diagnosis
The Nidek ARK-700 is a high-precision instrument engineered to meet the stringent demands of objective refraction and keratometric measurement in clinical environments. Utilizing infrared light technology, it projects slit beams onto the patient's retina and analyzes the reflected light through a photodetector sensor. This process, managed by a built-in microprocessor, enables precise calculation of refractive power—including sphere, cylinder, and axis—across multiple meridians.
Beyond refraction, the ARK-700 features an integrated keratometry module. This module projects luminous spots onto the corneal surface and measures the refracted images using linear CCD photoreceptors. The system detects the relative distances between the reflected spots with remarkable precision. The arrangement of photosensitive diodes allows for a detailed topographical analysis of the cornea along two principal meridians, with automatic calculation of the corneal cylinder axis.
A key advantage of this device lies in its auto-calibration mode for keratometry (KM auto-calibration). When reference spheres are placed in front of the eyepiece, the system performs ten successive measurements for each sphere, ensuring a margin of error below ±0.02 mm. This protocol significantly enhances result reproducibility, which is critical for longitudinal patient monitoring.
From an ergonomic perspective, the ARK-700 is operated using a joystick and a control display, providing precise alignment and easy result interpretation. The motorized movement system ensures smooth adjustments during measurements. Internal controls for brightness and contrast allow for personalized display optimization, enhancing user comfort.
Built with robust mechanics, the Nidek ARK-700 is designed to withstand intensive daily use. Its modular design permits recalibration or individual replacement of key internal components (such as the CCD sensor, measurement unit, or MIRE board), optimizing the device’s service life and making it ideally suited for ophthalmology clinics and hospital departments.
