NIDEK Auto Ref/Keratometer / Auto Refractometer ARK-1/AR-1

Large Pupil Zone Imaging Method

This 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. The pupil diameter is measured simultaneously. The difference of the measurement allows assessment of the effect of pupil size, such as vision in dim light.

Visual Description: Diagram showing pupil zone imaging for ARK-500/AR-300 series (Ø1 to 4 mm area) and ARK-1/AR-1 series (Ø1 to 6 mm area, Ø1 to 3.5 mm area).

Super Luminescent Diode and Highly Sensitive CCD

Incorporation of the Super Luminescent Diode (SLD) provides a sharper and clearer image compared to a conventional LED. The highly sensitive CCD detects the ring image even if the fundus reflection is weak. The system combining the SLD and highly sensitive CCD significantly improves measurement capability even in dense cataractous eyes.

Visual Description: Diagram illustrating the optical path including the eye, reflective mirror, emitted SLD light, ring image, ring lens, SLD, highly sensitive CCD, and simulated ring image. Images compare SLD and LED captured ring images for normal and cataractous eyes.

Optimal Fogging to Minimize Accommodation

(Available for the ARK-1s/1a and AR-1s/1a)

Fogging is performed after correcting the patient's astigmatism with built-in cylinder lenses. This allows the patient to view the target clearly and minimizes the interference with accommodation even in high astigmatism.

VA Measurement with Built-in Charts and Lenses

(Available for the ARK-1s and AR-1s)

The ARK-1s / AR-1s provides visual acuity (VA) measurement. This unique function enables a quick check of the patient's refractive error by comparing subjective measurement with objective measurement. Even corrected near visual acuity is measurable with easy operability to determine the need for a progressive lens.

Recall Function for Instant Vision Comparisons

(Available for the ARK-1s/1a/1 and AR-1s/1a)

The recall function provides the instant comparison between vision corrected with AR data and uncorrected vision or vision corrected with the data of patient's own glasses. For the patient, this function demonstrates the difference in vision and the necessity for more appropriate vision correction.

Visual Description: A table comparing different vision states: Distance vision corrected with AR data, Uncorrected distance vision, Distance vision corrected with LM data* (LM data imported from a NIDEK lensmeter), Uncorrected near vision, Near vision corrected with AR data, Near vision corrected with LM data*.

Contrast and Glare Test

(Available for the ARK-1s and AR-1s)

After a low contrast VA chart is projected, a glare source is projected beside the chart and the glare VA can be measured. With this test, the effect of glare and halo on visual performance can be measured. This utility can be used for cataract and refractive surgery patients.

Visual Description: Simulated patient vision of a low contrast VA chart, vision with glare and halo, and normal vision.

Keratometry Measurement with Mire Ring

(Available for the ARK-1s/1a/1)

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

Visual Description: Images showing keratometry measurement with four points and measurement with mire ring.

Accommodation Measurement with Artificial Intelligence Algorithm

Objective measurement of accommodation is performed with the patient focusing on a target which moves from distance to near. The artificial intelligence algorithm detects the patient's response and reduces the measurement time in cases with a slow or weak accommodative response. The accommodation measurement helps to assess pseudomyopia, eyestrain, and accommodative palsy.

Visual Description: Images of an accommodation graph (Amplitude of accommodation vs. Age) and a pupil diameter graph.

Measurement with Astigmatism Correction

Astigmatism is corrected with built-in cylinder lenses prior to measurement. It reduces the influence of astigmatism on the measurement of accommodation.

Assessment for Intermediate or Near Vision Lens

The assessment of accommodation based on the age-accommodation relation allows to suggest whether an intermediate or near lens is required.

Retroillumination Image and NIDEK Cataract Indices

(Available for the ARK-1s/1a and AR-1s/1a)

The retroillumination image enables the observation of opacity of the optical media of the eye. NIDEK cataract indices indicate the severity of the opacity and helps to assess the progression of pathology.

Visual Description: Images of "Eye with dense opacity" and "Eye with light opacity", showing retroillumination images with associated NIDEK Cataract Indices (COI.H, COI.A, POI).

Note: The NIDEK Cataract indices are for reference only. The following conditions may indicate different indices from ones of actual status: Peripheral image is darkly captured due to alignment position; Opacities are not in focus; Bright spot reflecting observation light occurs on the cornea apex; Position of the 3 mm diameter circle is shifted due to incorrect pupil detection caused by opacity location.

3-D* Auto Tracking and Auto Shot

The 3-D auto tracking and auto shot provide faster, simpler, and more accurate measurements. When alignment is performed correctly, measurement starts automatically. (*Y direction auto tracking is FOCUS available for the ARK-1 and AR-1).

Visual Description: Diagram showing the device's X and Y directions for auto tracking.

Tiltable Color LCD Screen

The color LCD with tilt function offers easy operation even when an operator is standing.

Visual Description: Image of the ophthalmic unit showing the tiltable color LCD screen.

High Speed Printer with Easy Loading & Auto Cutter

The printer paper can be changed easily. The data sheet is cut by an auto cutter for quick and easy detachment.

Visual Description: Image of the high-speed printer unit.

Summary Display and Printout of Measured Values

Various measured values can be displayed simultaneously on the summary screen, allowing easy and quick confirmation and printing.

Visual Description: An example of a summary display/printout showing various measurement values.

Eye Care Card System*

A card slot enables the use of an Eye Care card system, which provides quick and easy wireless data transfer. (*The card is optional).

Visual Description: A diagram illustrating the Eye Care Card System workflow, showing data transfer from the device to a card and then to a system.