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This kit is designed to clean pretty much anything you might put over your eyes — prescription eyewear, blue-light glasses, sunnies, virtual reality gear, even cameras and devices.
In the event that a spectacle wearer cannot obtain the eye relief that they require, some cameras and microscopes allow prescription lenses to be fitted onto their eyepieces. In this way, the user can temporarily dispense with glasses in favor of the lens mounted on the optics.
That distance is sometimes given on the filter in millimeters. A +3 close-up lens has a maximal working distance of 0.333 m or 333 mm. The magnification is the focal distance of the objective lens (f) divided by the focal distance of the close-up lens; i.e., the focal distance of the objective lens (in meters) multiplied by the diopter value (D) of the close-up lens:
Visual acuity with Distant chart with correctors Visual acuity with eye chart at Distant 20 feet (6 m) and with (cc: Latin cum correctore) correctors (spectacles); Dsc is without (sc: Latin sine correctore) correctors. See Visual_acuity#Legal_definitions: VA Nsc - VA Ncc Visual acuity with Near chart without correctors
A prescription of −1.00 +0.25 × 180 describes a lens that has a horizontal power of −1.00 D and a vertical power of −0.75 D. Only ophthalmologists write prescriptions in + cylinder. An optometrist would write a prescription in - (minus) cylinder. All spectacle and contact lenses would be made in minus cylinder.
One type of optical coating is an anti-reflective coating, which reduces unwanted reflections from surfaces, and is commonly used on spectacle and camera lenses. Another type is the high-reflector coating , which can be used to produce mirrors that reflect greater than 99.99% of the light that falls on them.
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Adjustable focus lenses, like single-focus lenses, also reduce image-jump and spatial distortion in the field of view associated with traditional multi-focal lenses. Additionally, the ideal near-vision correction can be achieved with precision, because the variable lenses emulate the focusing action of the youthful (non-presbyopic) eye.