Visionstar JS-2800

Abbe Number Compensation

Compensation is offered across an Abbe number range of 20 to 60, which is what allows high index materials to be read correctly rather than approximated.

Contact Lens Base Curve

Contact lenses are measured with base curve from 6.00 to 9.00, so a rigid fitting can be checked on the same instrument that verifies the spectacle lenses.

Cylinder, Addition and Axis

Cylinder runs 0 to plus or minus 10D and addition 0 to 10D, each selectable at 0.01, 0.12 or 0.25D, with axis across 0 to 180 degrees in 1 degree steps.

Tinted Lens Measurement

Coloured lenses are measurable above 10 per cent transmittance, the card noting that 20 per cent and over applies for powers between 15D and 25D.

Full Lens Type Coverage

Single vision, bifocal, trifocal, progressive power and contact lenses are all named as measurable, alongside pupil distance, pupil height and lens diameter.

Wide Lens Acceptance

Lens diameter reaches approximately 120mm at maximum, which takes uncut blanks as well as the finished lenses that a practice more usually presents.

Backlit Graphic Display

The display is a full graphic black and white LCD at 320 by 240 with a backlight, which keeps it readable in a dimly lit consulting room during a measurement.

Built In Printer

A built-in thermosensitive printer is fitted, taking paper of 38mm width, so a measurement is recorded on paper at the instrument rather than copied out by hand.

High Index Lens Dispensing

Abbe compensation from 20 to 60 is the whole reason to choose this particular instrument. High index materials disperse light differently from ordinary crown glass, and an instrument that assumes one figure reads them approximately. For a practice dispensing thinned lenses against strong prescriptions, being able to set the constant to the material is what makes a verification actually mean something at all for a strong prescription.

Weak Cylinder Verification

The manufacturer claims a superior astigmatism accuracy on the low reading lenses under 0.25D. Weak cylinders are where measurement error matters proportionally most, since a quarter dioptre of astigmatism read as a half is a large relative mistake indeed. That claim belongs to the manufacturer, so it is worth testing against a lens of known power before relying upon it in daily practice.

Brightly Lit Consulting Rooms

Performance is described as being free from interruption by environmental light. A bench beside a window, or under bright clinical lighting, otherwise causes real trouble on some instruments, and the backlit display covers the opposite case of a dimly lit room. Between them, the two provisions suit a practice whose lighting is not ideal and cannot easily be changed to suit an instrument.

Tinted and Contact Lens Work

Coloured lenses above 10 per cent transmittance, and contact lenses with base curve from 6.00 to 9.00, are both covered here. That suits any practice dispensing sunglasses and fitting contact lenses alongside ordinary spectacles, since all three can be verified at one bench rather than requiring separate equipment for each of the different jobs that it happens to do.

The Material Is Accounted For

Abbe compensation across 20 to 60 addresses something that most lensmeters simply assume. A high index lens does not behave like crown glass, and reading it as though it does introduces an error that grows with the power of the lens itself. For a practice thinning strong prescriptions, setting the constant to the actual material is the difference between a real verification and an approximation quietly dressed up as one.

Readable in Any Room

A backlit display for the dim rooms, and stated immunity to environmental light for the bright ones, together cover the lighting a practice actually has, and not the lighting a specification assumes. Very few benches sit in genuinely ideal conditions, and an instrument that works beside a window and in a dim back room removes a practical constraint on where the instrument can usefully be placed within a practice.

Everything Verified at One Bench

Single vision, bifocal, trifocal, progressive, contact and tinted lenses are all of them named as measurable, with pupil distance and pupil height alongside them. Any practice covering that range of work would otherwise need more than one instrument, so consolidating it saves both the outlay and the bench space that a second machine would otherwise occupy within an already crowded consulting room.

The Visionstar JS-2800 offers Abbe number compensation from 20 to 60, with cylinder from 0 to plus or minus 10D and addition from 0 to 10D, each selectable at 0.01, 0.12 or 0.25D, and axis across 0 to 180 degrees. Contact lenses are measured with base curve from 6.00 to 9.00, coloured lenses above 10 per cent transmittance, and lens diameter reaches approximately 120mm. Single vision, bifocal, trifocal, progressive and contact lenses are all named as measurable, alongside pupil distance and pupil height. The display is a backlit 320 by 240 graphic LCD and a built-in thermosensitive printer takes 38mm paper.

Three rows on the card need confirming before an order. Sphere is printed as 0 to plus 25D, which read literally would exclude every minus lens, while the contact lens row on the same card gives plus or minus 25D. The prism row gives steps without a clear upper limit and mixes its units. The PD row gives a single figure rather than a range. Separately, the accuracy and environmental light claims are the manufacturer's own, reported here rather than endorsed, and a second model is named without any stated difference.

If your practice dispenses high index lenses, verifies weak cylinders, or works in a room whose lighting is less than ideal, speak to Medigear.uk. As a verified medical equipment supplier working across medical, dental, rehabilitation and aquatic therapy settings, the team will confirm the corrected specification.