Nidek ARK-1s


Opthalmic Instrument and Nidek are proud and excited to announce the newest autorefractor/autokeratometer available. The ARK-1s measures objective spherical, cylindrical refractive errors and cylinder axis from the refractive status of the patient's eye. In addition, this is the first ARK that combines the capability of glare testing with, low contrast testing, accommodation, retro-illumination, visual acuity chart presentation and the ability to subjectively refine the sphere.

The glare testing capability makes it easier to test patients with cataracts. Traditional methods can be cumbersome and time consuming with questionable accuracy. With Medicare cuts prevailing, it is important to have a consistent measurement to help accurately qualify patients for cataract surgery. For doctors who also use low contrast testing for their patients, the ARK-1s has the capability. The accommodative measurement helps doctors to detect problems in pre-presbyopia, latent hyperopes, and children that have trouble reading. The retro-illumination modality helps to educate patients, with an actual image of their cataract progression.

This all-in-one compact design has Nidek/Marco's famous auto alignment EyeTracking System on the X-Y-Z axis for consistent, accurate readings.


Accurate refraction measurement

Large pupil zone imaging method

The large pupil zone imaging method enables the measurement of wide area refraction of up to 6 mm diameter and can indicate the difference between wide area refraction and the central area refraction of up to 3.5 mm diameter.

SLD and highly sensitive CCD

The system combining the Super Luminescent Diode (SLD) and highly sensitive CCD significantly improves measurement capability even in dense cataractous eyes.

Optimal fogging to minimize accommodation (available for the ARK-1s and ARK-1a)

The Fogging allows the patient to view the target clearly and minimizes the interference with accommodation even in high astigmatism.

VA measurement with glare test (available for the ARK-1s)

The ARK-1s provides visual acuity (VA) measurement. A glare source is projected beside the chart and the glare VA can be measured.

Simulated patient vision of VA chart and glare source
Vision with glare and halo
Normal Vision

Simple opacity assessment with retroillumination image (available for the ARK-1s and ARK-1a)

The retro illumination image enables the observation of opacity of the optical media of the eye.

Eye with dense opacity
Eye with light opacity

Patient-friendly accommodation measurement (available for the ARK-1s and ARK-1a)

Objective measurement of accommodation is performed with patient's focusing on a target which moves from distance to near.

Keratometry measurement with mire ring

The mire ring is used to measure keratometry. It reduces eyelid artifacts.