OPTICIANS EVALUATION EXAM 2026 QUESTIONS AND
SOLUTIONS RATED A+
✔✔Datum length - ✔✔The horizontal width of a lens or lens opening as measured along
the datum line.
✔✔First focal length - ✔✔For a thin lens, the distance from the lens to the first principal
focus.
✔✔Second focal length - ✔✔For a thin lens, the distance from the lens to the second
principal focus.
✔✔Overall temple length - ✔✔The length of a spectacle lens temple as measured from
the center of the hinge barrel, around the temple bend, to the posterior end of the
temple.
✔✔Length-to-bend (LTB) - ✔✔Temple length measured from the center of the hinge
barrel to the middle of the bend.
✔✔Aspheric lenticular lens - ✔✔A lenticular lens whose optically usable central portion
has a front surface with a changing radius of curvature. The farther from the center of
the lens, the longer the front surface radius of curvature becomes..
✔✔Blended myodisc lens - ✔✔A minus, lenticular in design, with the edges of the bowl
blended so as to improve the cosmetic aspects of the lens.
✔✔Corrected curve lens - ✔✔A lens whose surface curvatures have been carefully
chosen to reduce those peripheral lens aberration that are troublesome to the spectacle
lens wearer.
Synonym: best form lens.
✔✔Cover lens - ✔✔A thin lens that is temporarily glued to the surface of a semifinished
blank to protect the surface of teh lens and facilitate accurate grinding, as in the case of
a slab-off grind on a glass lens.
✔✔Vertex distance - ✔✔The distance from the back surface of the lens to the front of
the eye.
✔✔Double-D lens - ✔✔A multifocal lens with a flat-top bifocal-style segment in the lower
portion of the lens and an inverted flat top bifocal-style segment in the upper portion of
the lens.
, ✔✔Finished lens - ✔✔A spectacle lens that has been surfaced on both front and back
to the needed power and thickness. A finished lens has not been edged for a spectacle
frame but is still in uncut form.
✔✔Fresnel lens - ✔✔A lens made from a thin flexible plastic material, having concentric
rings of ever-increasing prismatic effect that duplicates the refractive effect of a powered
spectacle lens.
✔✔Glare-control lens - ✔✔Present use of the term denotes a lens that absorbs
wavelengths toward the blue end of the spectrum, reducing glare from short, visible
wavelength light.
✔✔Glazed lens - ✔✔Often used in reference to the thin plastic demonstration lens that
comes in a pair of spectacle frames.
Synonym: dummy lens.
✔✔Gradient lens - ✔✔A lens having a tinted upper portion that gradually lightens
toward the lower portion of the lens.
✔✔Laminated lens - ✔✔An ophthalmic lens that is made up of more than one layer.
Examples include polarized lenses, lenses that have a glass front and a polyurethane
back surface, and plastic bifocal lenses made from front and back sections to bypass
conventional surfacing procedures.
✔✔Lenticular lens - ✔✔A high-powered lens with the desired prescription power found
only in the central portion. The outer carrier portion is ground so as to reduce edge
thickness and weight in minus prescriptions and center thickness and weight in plus
prescriptions.
✔✔Meniscus lens - ✔✔A lens having a convex front surface and a concave back
surface.
✔✔Mineral lens - ✔✔Synonym for glass lens.
✔✔Minus lenticular lens - ✔✔A high minus lens that is lenticular in design, having a
central area containing the prescribed refractive power and a peripheral carrier that is
plus in power for maximum edge thinning.
✔✔Multidrop lens - ✔✔A high plus, full-field aspheric lens in which the surface power
drops rapidly as the edge of the lens is approached.
✔✔Myodisc lens - ✔✔(1) Traditional definition: a high minus lens that is lenticular in
design, having a central area containing the prescribed refractive power and a
peripheral carrier that is plano in power. The front curve is either plano in power or very
close to plano. (2) General usage: any high minus lens that is lenticular in design.
SOLUTIONS RATED A+
✔✔Datum length - ✔✔The horizontal width of a lens or lens opening as measured along
the datum line.
✔✔First focal length - ✔✔For a thin lens, the distance from the lens to the first principal
focus.
✔✔Second focal length - ✔✔For a thin lens, the distance from the lens to the second
principal focus.
✔✔Overall temple length - ✔✔The length of a spectacle lens temple as measured from
the center of the hinge barrel, around the temple bend, to the posterior end of the
temple.
✔✔Length-to-bend (LTB) - ✔✔Temple length measured from the center of the hinge
barrel to the middle of the bend.
✔✔Aspheric lenticular lens - ✔✔A lenticular lens whose optically usable central portion
has a front surface with a changing radius of curvature. The farther from the center of
the lens, the longer the front surface radius of curvature becomes..
✔✔Blended myodisc lens - ✔✔A minus, lenticular in design, with the edges of the bowl
blended so as to improve the cosmetic aspects of the lens.
✔✔Corrected curve lens - ✔✔A lens whose surface curvatures have been carefully
chosen to reduce those peripheral lens aberration that are troublesome to the spectacle
lens wearer.
Synonym: best form lens.
✔✔Cover lens - ✔✔A thin lens that is temporarily glued to the surface of a semifinished
blank to protect the surface of teh lens and facilitate accurate grinding, as in the case of
a slab-off grind on a glass lens.
✔✔Vertex distance - ✔✔The distance from the back surface of the lens to the front of
the eye.
✔✔Double-D lens - ✔✔A multifocal lens with a flat-top bifocal-style segment in the lower
portion of the lens and an inverted flat top bifocal-style segment in the upper portion of
the lens.
, ✔✔Finished lens - ✔✔A spectacle lens that has been surfaced on both front and back
to the needed power and thickness. A finished lens has not been edged for a spectacle
frame but is still in uncut form.
✔✔Fresnel lens - ✔✔A lens made from a thin flexible plastic material, having concentric
rings of ever-increasing prismatic effect that duplicates the refractive effect of a powered
spectacle lens.
✔✔Glare-control lens - ✔✔Present use of the term denotes a lens that absorbs
wavelengths toward the blue end of the spectrum, reducing glare from short, visible
wavelength light.
✔✔Glazed lens - ✔✔Often used in reference to the thin plastic demonstration lens that
comes in a pair of spectacle frames.
Synonym: dummy lens.
✔✔Gradient lens - ✔✔A lens having a tinted upper portion that gradually lightens
toward the lower portion of the lens.
✔✔Laminated lens - ✔✔An ophthalmic lens that is made up of more than one layer.
Examples include polarized lenses, lenses that have a glass front and a polyurethane
back surface, and plastic bifocal lenses made from front and back sections to bypass
conventional surfacing procedures.
✔✔Lenticular lens - ✔✔A high-powered lens with the desired prescription power found
only in the central portion. The outer carrier portion is ground so as to reduce edge
thickness and weight in minus prescriptions and center thickness and weight in plus
prescriptions.
✔✔Meniscus lens - ✔✔A lens having a convex front surface and a concave back
surface.
✔✔Mineral lens - ✔✔Synonym for glass lens.
✔✔Minus lenticular lens - ✔✔A high minus lens that is lenticular in design, having a
central area containing the prescribed refractive power and a peripheral carrier that is
plus in power for maximum edge thinning.
✔✔Multidrop lens - ✔✔A high plus, full-field aspheric lens in which the surface power
drops rapidly as the edge of the lens is approached.
✔✔Myodisc lens - ✔✔(1) Traditional definition: a high minus lens that is lenticular in
design, having a central area containing the prescribed refractive power and a
peripheral carrier that is plano in power. The front curve is either plano in power or very
close to plano. (2) General usage: any high minus lens that is lenticular in design.
