When it comes to matters of the eye, accurate focus and magnification are the name of the game. Luckily, Vermont Photonics has devices known as dioptometers and dynameters, which can be used to measure and calibrate the focal power of a lens and measure the range of both focus and magnification. If you use an instrument or optic with an eyepiece, Möller-Wedel Optical dioptometers and dynameters from Vermont Photonics can help you calibrate and accurately set your eyepieces.

How To Use a Vermont Photonics Dioptometer

With a dioptometer, also referred to as a diopter telescope, in hand, you can measure the focal power of a lens in a few simple steps. First, look through the dioptometer at a uniform colored wall with the focus ring set to zero, and rotate the eyepiece of the diopter telescope until its reticle is in focus. Then, place the dioptometer on the eyepiece or telescope that you are testing. This time, the eyepiece of the telescope will be rotated until the reticle is in focus. The result will be the eyepiece being set to zero.

DioptometerWant to measure the focus range of your eyepiece? Rotate the eyepiece you’re testing to the last gradation of its scale or the end of its travel, focus the dioptometer using the focus ring, and take your reading from the diopter graduated scale. Rotate the eyepiece to the opposite end of its scale, adjust the dioptometer until the reticle is in focus, and read the diopter setting off the scale. You now have the full range of adjustability of your eyepiece and an accurate location for the zero setting.

How to use a Vermont Photonics Dynameter

Used for measuring eye relief distance and exit pupil diameter, our Möller-Wedel Optical dynameters are operated very similarly to the dioptometer. Follow the same course of action as you did for the dioptometer, focusing the dynameter first and then using it to measure the system you’re testing. The major difference between the two instruments is that the dynameter has a graduated eyepiece reticle that allows the user to measure the diameter of the exit pupil. Comparing the measured diameter of the exit pupil in the dynameter with the actual exit pupil size gives a measure fo the magnification. Eye relief can be measured directly off the vertical scale on the dynameter after adjusting it until the exit pupil is in best focus.

Applications for Dynameters and Dioptometers

These Vermont Photonics devices can be put to use anywhere eyepieces need to be adjusted, calibrated, or characterized. For example, rifle manufacturers will use dioptometers and dynameters to test the range of rifle scopes eyepiece settings and eye reliefs. They’re also used in the medical field for devices such as endoscopes and microscopes.

With its high accuracy, large range, and ease of use, Vermont Photonics’s dioptometers and dynameters are the preferred instrument for anyone looking to measure and adjust the focal power of a lens. To discover more about our dioptometers and dynameters, please visit our product pages.