ABO

UV radiation Radiation type of wavelengths shorter than 400 nm UV C Division of UV radiation ranging from 290-200 nm & is extremely dangerous, absorbed by the ozone layer UV B Division of UV radiation ranging from 320-290 nm & causing sunburn, corneal burn, retinal damage, & eventually cataracts; mainly absorbed by the cornea & partly the crystalline lens UV A Division of UV radiation ranging 400-320 nm & causing suntan & cataracts; primarily absorbed by the crystalline ...

This allows dispensers to avoid being directed to a poor decision by a patient who has no optical experience control A pair of eyeglasses achieves perfection if it succeeds in these three areas: good optics, good wearing comfort, and good cosmetics The patient has a great deal of ________ invested in you, and you must be willing to handle each prescription with the full accumulation of our knowledge and skills trust The purpose of power dispensing is to make patients awar...

bulbar conjunctiva Vascular, transparent membrane that covers the white sclera. Protects and lubricants the eyeball ciliary body Responsible for focusing at near objects. Makes the lens take on a thin/thick shape with muscular power to be able to alter the shape of the lens. Connected with the choroid. Cornea Transparent part of the eye that covers the iris and the pupil. Helps focus the light entering the pupil. Kept moist with a thin layer of tears and polished by eyelid movem...

Visible Spectrum of light 390 -750 Nanometers Long Ultraviolet (UV) Light 396-400 Nanometers Light is always bent towards the _______ of a Prism Base 1 Inch 25.4 millimeters I meter 39.37 inches Wavelength The distance between two corresponding parts of a wave two negative numbers when multiplied equal a ____ number positive Wave Theory Christian Huygens late 1600s -describes light as moving in waves, like waves of water corpuscular...

When taking seg height measurements, which of the following situations could result in a parallax error? Patient sitting/ dispenser standing erect Which of the following is not significant in identifying the problem of vertical imbalance? Patient's age Which of the following elements is NOT critical when determining vertical imbalance? Lens power in the 180 degree meridian A prism will displace the object being viewed towards its ________. Apex A prism will bend ...

Light falling on the front surface of a spectacle lens is: A) partially reflected, partially absorbed and the remainder refracted B) partially reflected and the remainder refracted C) partially absorbed and the remainder refracted D) totally refracted A) partially reflected, partially absorbed and the remainder refracted Concave mirror: A) can focus parallel incident rays to form a real image B) can focus parallel incident Rays to form a virtual image C) always produce inverted im...

Fibrous Tunic Vascular Tunic Nervous Tunic What three layers are the eye made up of? Fibrous Tunic Consists of the sclera and the cornea. Vascular Tunic Consists of the iris, the choroid, and the ciliary body and is responsible for nourishment Nervous Tunic The inner layer of photoreceptors and neurons which consists of the retina; Contains rods and cones Rods Lets us see at twilight and in dimly lit rooms; does not discriminate between different colors of light. Abo...

Cancelling effect- subtract prism amounts BU/BU BD/BD BI/BO Powers between 0.00 & +/- 3.00 Read in 1/8 diopters .12 .37 .62 .87 Lensometer is also referred to as Lensmeter, focimeter, vertometer To focus eyepiece 1) while turned off. Place white sheet of paper against lens stop. 2) turn focus ring all the way counter clockwise,and then back clockwise until sharp. 3) remove paper and turn lensometer on 4) move power drum to high plus, then turn away from you unti...

To what does a ptosis crutch give support? -Upper Lid. How is a lens' focal LENGTH altered? -Changing the curvature of one surface. Which instrument measures vertex distance? -Distometer. What controls the amount of light that enters the eye? -Iris. Which word is used to describe light's changing direction as it passes from one medium to another? -Refraction. Frame materials are available in which two forms? -Metal and plastic. Meniscus, equiconc...

The extra-ocular muscles are inserted into the sclera and serve to rotate the eye in all possible directions. There are _______of these muscles. Six The fibrous tunic is comprised of the: Sclera and cornea Fusion occurs: In the brain The aqueous fluid is continually being manufactured by: The ciliary body The ability of the eye to bring objects of varying distances to focus on the retina is known as: Accommodation When accommodation is at rest, rays of lig...