ABO 2023 with verified questions and answers

Visable spectrum of light 380 nm - 760 nm Amplitude Vertical distance from trough to crest ASIM American Society of Testing Materials ANSI American National Standards Institute OSHA Occupational Safety and Health Administration FDA Food and Drug Administration FTC Federal Trade Commission Inverted triangle/diamond Unobtrusive frame, light or medium weight frame, lighter color, rounded lens shape, delicate characteristics of frame for women Base down triangular Fit size to largest part of lower facial area, dark colors or bolder look Round/square Narrow frame, high temple attachment Oblong Deep frame, low temple attachment Oval Many wear most any type Trivex Pros: better optical quality than poly, impact resistant, tintable, lightest material on market, uv protection, high tensile strength Cons: susceptible to scratch Trivex Index of Refraction 1.53 Hi-index Pros: thinner and lighter than glass and plastic, better optical quality than poly Cons: susceptible to scratch, high chromatic abberation Hi-index Index of Refraction 1.60, 1.66, 1.70 Hi-index Abbe 42 (1.60), 32 (1.66) Polycarbonate Pros: thinner and lighter than glass and plastic, highly impact resistant, inherent uv protection Cons: poor optical quality, susceptible to scratch, susceptible to stress fractures in drill mount, doesn't readily accept tint Polycarbonate index of refraction 1.59 Polycarbonate Abbe 29 CR-39 Pros: 50% lighter than glass, readily tintable, less likely to fog Cons: susceptible to scratch, high IOR makes less suitable for high Rx CR-39 Index of Refraction 1.498 CR-39 Abbe 58 Crown glass Pros: superior optics, stable material, scratch resistant Cons: does not accept tint, not impact resistant, heavy Crown glass index of refraction 1.52 Crown glass Abbe 59 Trivex Abbe 46 Polycarbonate Frame Primarily for sport or safety, resists adjustment Rubber frame Flexible, not adjustable Pure nickel frame Resists corrosion, easily adjusted Nickel silvers Holds shape best of any metal combination, most popular metal for eyeglass frames Monel metal Whitish in color, pliable for good adjustment, resists corrosion, mostly used for temples, bridges, and fronts Aluminum frame Can be finished in a wide variety of colors, does not corrode Stainless steel Well suited for temples Titanium Extremely light in weight, very strong and flexible, very corrosion resistant, hypoallergenic, hard to solder or weld Photochromatic glass Made with silver halide crystals that respond to uv Cellulose aceto-propionate Made with granules of the material that are heated until liquid and then injection molded to desired frame shape, lighter than cellulose acetate cellulose acetate Can be formed into sheets of plastic from which frame parts are cut, can be made into granules used for injection molding, thermoplastic Thermoplastic Does not have plastic memory Thermoelastic Returns to original shape when reheated Optyl Liquid resin and hardener mixed and drawn into frame molds using a vacuum process, thermoelastic Aspheric Lens surface gets progressively flatter from center to edge, thinner, less magnification, improves optics, cannot be measured with lens clock, not exempt from drop ball testing Kevlar Becomes pliable with heat, will not shrink or stretch Nylon Loses high flexibility if not soaked in water overnight periodically Polarized lenses Reduce glare from water, snow, or metallic surfaces, can't be worn for certain types of skiing Bifocals The greater the power of the add and/or the optical center of the segment is from the transition line, the greater the amount of image jump Progressive lenses No image jump Intermediate zone Add 1/2 of the add power to the sphere Monocular PD Distance from the center of the bridge of the node to the center of each pupil, done for progressives or high rx Skull temple Bends down behind the ear and follows the contour of the skull, resting evenly against it Library temples Generally straight back and hold the spectacles on primarily by pressure against the side of the head Convertible temples Can be used as library or skull depending on how they are bent Riding bow Curve around the ear to the level of the earlobe, used most frequently in children's and safety frames Comfort cable Similar to riding bow, constructed from metal flexible coiled cable Balgrip mounting Secure the lens in place with clips that attach to a bar of tensile steel that fits into a nasal and temporal notch on each side of the lens Polyamide/copolyamide 72% lighter than cellulose acetate, can be made opaque or translucent Grilamid Used in sport and performance type of eyewear Carbon fiber Not adjustable, lightweight, may break in cold weather SSS The shorter the radius the steeper the curve, the steeper the curve the higher the power, the higher the power the thicker the lens Polariscope Reveals case hardening of a glass lens Topogometer Attachment to make keratometer more accurate Lens equilibration Takes about 20 minutes, necessary for frame to reach 98.6 degrees, the tear film assists in equilibration Penetrating keratoplasty The full thickness of the cornea is removed and replaced with donor tissue Fitting cross of a progressive lens location 2 to 4mm above the MRP Flint glass Used for fused bifocal, natural yellow tint Used to create iseikonic lenses Index of refraction, lens thickness, vertex distance Axial eye deficiency The globe is too large Distance PD Not a standard measuremeny for bifocals No image jump Flat top 45, executive style, progressive acanthamoeba keratitis Infection of the eye that can result in permanent visual impairment or blindness ISO International Organization for Standardization Tarsus plate Part of the eyelid made of fibrous connective tissue and forms the supporting structure for the lid Myodisc lens Biconcave, front curve - 0.50 Ocular curve Always - Corrected curve lenses Increase the useful area of the lens FPD (GCD) A + DBL Horizontal Decentration (FPD - PPD)/2, if frame PD is bigger decentration is in Minimum blank size GCD - PD + ED Vertical gradient Tutone, becomes lighter near nasal area Horizontal gradient Frame lightens from top to bottom Hibo Temples higher than regular placement but not all the way to the top Fulvue Temples at uppermost point on frame Chappel pliers Cut temples and screws End piece angling pliers Open or close the end piece in or out from the side of the skull Parallel jaw pliers Used to increase or decrease pantoscopic tilt Round-flat pliers Adjust American style frame nose pieces Hollow snipe pliers Adjust pad arms Dry edgers Used to cut certain plastic lenses, especially polycarbonate Wet edgers Used to cut certain plastic lenses, not meant to cut polycarbonate Hand edger Commonly used to reduce bevel Groove maker Creates groove in edge of lens Drill pliers Creates holes in rimless lenses Boxing system Measures a lens as it will be placed in the eye wire, and creates horizontal and vertical lines tangent to farthest edges of the lens Mechanical PD Distance between optical centers, should equal PD Record retention 3+ years depending on state law, 10 years for Medicare patients EPO Exclusive Provider Organization PPO Perferred Provider plan HMO health maintenance organization Vertical decentration Seg height - (B/2) Total decentration FPD - PPD -4.25D to - 7.00D 2.50 base curve -2.25D to - 4.00 D 4.00 base curve Prism Prism = 1cm/1m 2.25D to 4.50D 8.00 base curve 2.00D to - 2.00D 6.00 base curve -7.25D to - 12.00D 0.50 base curve 1 meter 100 centimeters, 1000 mm, 40 in Base curve Front curve + back curve = total power Prism Formula (f x Cmm) /10 Plus lens decentration Shifts with lens +8.00D to +4.75D 10D base curve Addition Down/up, up/down, in/in, out/out FBI If the frame add is bigger than the PPD the lens is moved in Cancel Down/down, up/up, out/in, in/out Create prescribed prism (prism x 10)/diopter Focal length 1m/D Minus lens decentration Decentration shifts opposite lens Spherical equivalent 1/2 cylinder + sphere Grey Best for color deficient person, most popular sunlens color Photochromatic Main ingredient silver halide, do not darken as much on hot days Blu-blockers Eliminates light in spectrum below 500nm, orange to orange brown in color, do affect color perception AR coating advantages 1/4 wavelength thick, increased transmission, good for high index lenses, decreased indoor and outdoor glare, better night vision, loss of halos and flares, less surface lens reflection, reduces appearance of thickness Executive lens Bifocal across entire bottom of lens, no image jump Seg drop Difference between the MRP on the lens and the top of the segmeng G15 Green lens with 15% Grey addition, popular in sunglasses Green Absorbs UV and infrared, popular for sunglasses Brown/brown grey Improves contrast on bright but hazy surrounding Pink/rose Reduces indoor glare, does not cause color distortion Safety lens Polycarbonate, 3mm thickness, lenses must be marked with ID of the manufacturer on the upper edge of each lens, must say z87 Chemical treating Glass lenses less than +/- 7.00D should be chemically treated only, lenses are immersed in molten salt/potassium nitrate, process takes around 16 hours Heat treating Increases impact resist on glass, heat lenses two to three minutes then rapidly cool with air blower Flint glass index of refraction 1.80 Cylinder lens Has no power at the axis and full power 90 degrees away from axis Geneva standard index 1.53 Lens calipers Measures thickness of lenses in mm Lens clock Checks for warped lenses, measures curvature of a surface Distometer Measures vertex distance Front curve of myodisc lens -0.50 60/120 degrees 75% of cylinder power felt 45/135 degrees 50% of cylinder power felt 30/150 degrees 25% of cylinder power felt Minimum lens thickness US 1mm Most chromatic abberation Flint glass ABBE number Measures possible chromatic abberation in a lens material, the higher the index the lower the abbe number the more abberation Drop ball test 5/8 in 16g steel ball dropped from 50in, 1in ball for safety lenses Disadvantages of AR Harder to keep clean, mishandling lenses can damage coating, cost Seg width The widest horizontal dimension of the bifocal segment Seg depth Longest vertical dimension of a bifocal segment Seg height Measurement taken vertically from the lowest point on the lens to the top of the segment Blended bifocal Round segment bifocal, high image jump, fit 1-2mm higher than your seg measurement