The Sharp VA software can be calibrated for the above effective viewing distances in both Mirror and Direct view setups (6" increments).
If your monitor is not on this list, a clinically accurate calibration may still be obtained. Please inquire prior to purchase.
Why do monitor sizes have different calibration ranges?
Monitor size limitations have been imposed to protect the quality and accuracy of our system. We have done extensive clinical research on our software, and the effects of different monitor sizes and working distances. We have found that with certain patient types (corneal issues, cataracts, amblyopia), too much blank white space on a screen can induce veiling glare, thus reducing one's measured visual acuity. For example, if you have a very small exam room, there will be an upper limit on the monitor size you can use. This limit has been imposed to prevent veiling glare in certain patient populations. At the same rate, a very small monitor with a large working distance may be too small to present larger optotypes. Please follow the referenced guidelines, and feel free to contact us with any questions.