Nidek OPD-Scan II ARK-10000

The ARK-10000 fits ophthalmology clinics, optometry practices and refractive surgery assessment rooms. A technician seats the patient at the chin rest, brings the eye into view with the joystick and runs the exam from the touch screen, so one measurement session can feed several members of the clinical team. ARK mode returns refraction and keratometry quickly for routine visits, while ARK/CT mode adds the corneal maps for detailed work.

For refraction, the autorefraction result gives sphere, cylinder and axis across a wide band, including high cylinder. For corneal assessment, the axial, instantaneous, refractive and elevation maps show curvature and shape over a 0.5 to 11.0 mm diameter, and the keratometry values come from the same ring image. The eye image captured at measurement shows the eye as it was measured, so corneal or lens opacities appear next to the maps. Pupil size under photopic and mesopic conditions is recorded in the same exam.

Wavefront and OPD maps help clinicians assess the total aberration pattern of a patient's eye and how much of it arises in the cornea. Final Fit software imports ARK-10000 data to simulate postoperative corneal shape and generate shot data for the EC-5000 excimer laser, which places the analyser inside surgical planning workflows. Optional wavefront contact lens measurement and accommodation measurement extend the exam for contact lens fitting and accommodation work.

Results stay with the patient file in the built-in database. They can be exported to a refractor or an Eye Care Card, and OPD-Station lets other computers on a local network open the same data for analysis.

Five measurements from one patient position

Refraction, corneal topography, wavefront analysis, keratometry and pupil size come from one chin rest. A single positioning step feeds every map, which reduces repositioning during the visit.

Corneal and internal contributions shown apart

The internal OPD map removes corneal power from the total error. Clinicians see the cornea's share and the internal share as separate maps.

Repeated readings, one selected automatically

Each exam runs several measurements, and the instrument selects the best one. Daily results stay consistent for the operator, with no extra steps.

Sphere to +22 D and cylinder to ±12 D

The measuring range reaches −20.00 to +22.00 D in sphere and 0.00 to ±12.00 D in cylinder. High-power and high-cylinder eyes sit within the working range.

Readings in under 0.4 seconds

Dynamic skiascopy captures 1,440 points in under 0.4 seconds. Short capture times suit a busy clinic schedule.

Forehead rest shaped for eyelid access

The forehead rest lets the operator reach the patient's eyelids and keep them open. Clear access to the eye supports a clean placido ring image.

Data held locally and shared on a network.

A built-in database, a detachable hard drive and a floppy disk drive hold exam data. A network connection lets OPD-Station on another computer analyse it.

Upkeep centred on paper, cleaning and calibration

Routine upkeep covers printer paper, chin rest paper, window and ring cleaning, and the instrument's built-in accuracy checks and CT calibration routines. Backup of exam data to external storage completes the routine.

Options for accommodation and contact lens work

Accommodation measurement and wavefront contact lens measurement extend the standard exam as options. Corneal Navigator software and a colour printer for corneal maps are also available.

Skiascopic phase-difference refraction

A weak infrared slit beam scans the retina while photodetectors capture the reflected light. The skiascopic phase-difference principle produces the refractive error map.

1,440-point measurement

Each measurement samples 1,440 points (4 × 360) across a 2.0 to 6.0 mm zone. Dynamic automatic refraction completes the capture in under 0.4 seconds.

OPD map in dioptres

The OPD map plots the refractive error distribution of the whole eye, including lower- and higher-order terms, in dioptres. One look shows theeye's refractive status.

Internal OPD map

The map subtracts corneal refractive power from the total OPD. What remains describes the eye's internal optics.

Wavefront maps and Zernike graph

Wavefront high-order, total and group maps sit beside a Zernike graph with RMS and coefficient views. A point spread function display completes the aberration set.

Placido corneal topography

Reflected Placido rings are captured and analysed to plot corneal contour, shape and refractive power. The measuring diameter spans 0.5 to 11.0 mm over a 10 to 100 D range.

Axial, instantaneous, refractive and elevation maps

Four corneal map types show curvature, local change, refractive power and surface height. Target refractive and difference maps add comparison views between exams.

Eye image with photopic and mesopic views

The image taken at measurement shows the eye itself, with photopic, mesopic and placido ring views. Corneal and lens opacities become visible next to the maps.

Keratometry from the ring image

The system simulates keratometry data from the captured placido ring image. The same exam therefore returns keratometry and topography together.

Colour touch screen and joystick

The operator controls the exam through the colour LCD touch screen and positions the eye with the joystick. A touch-screen pen is included.

Built-in printer

The built-in printer prints refraction data. A colour printer is available as an option for corneal maps.

Database, hard drive and floppy disk

The built-in database stores exams for later display as colour maps. A detachable hard drive and a floppy disk drive carry data between systems.

Network analysis with OPD-Station

OPD-Station runs on an independent PC, reads data measured by the ARK-10000, displays the maps and manages the data. The database can be shared across a local network.

Data transfer to a refractor

Day and night measurement data can also be sent directly to a refractor. An Eye Care Card provides a second route for the same export.

Final Fit planning software

Final Fit imports ARK-10000 measurements and simulates postoperative corneal shape from entered correction amounts. It also generates shot data for the EC-5000 excimer laser.

The ARK-10000 suits ophthalmology clinics and optometry practices that want refractive, corneal, and wavefront data from one chin rest. Its internal OPD map is the deciding feature: with the corneal contribution removed from the total error, a clinician can place a problem in the cornea or inside the eye straight away. Refractive surgery teams using Final Fit and the EC-5000 laser get a measurement source that feeds directly into planning. Smaller practices that need only keratometry and refraction can run ARK mode and save topography for later exams. Whichever mode is chosen, the instrument runs on 100/120 or 220/240 V AC at 170 VA and weighs 25 kg.