Trial lens Set Flashcards
A tool used by optos to determine a patients eye refraction either in the form of eyeglasses or contact lenses
Trial box
Trial case
Trial lens
It measure/check refractive error
Trial lens
Objective refraction
No need for response
Subjective refraction
Need response
For diplopia charting
Trial lens
Assess binocular vision
Trial lens
Measure lenses (hand neutralization)
Trial lens
Contents or accessories of trial set
Trial frame
Trial lenses
Prisms
JCC
Frosted lens
Plano lens
Red green cobalt blue filter
Red white maddox rod
Stenopaic slit
Occluder
Pinhole
Near VA chart
PD rule
an eyeglass frame designed to permit insertion of different lenses used in correcting refractive errors of vision
Trial frame
4-5 components
1- high powered lens
2- spherical lens
3- cylindrical lens
4- accessory and prisms
Accommodates up to five, 38mm lenses for each eye
Full aperture frame
Independent screw adjustment for PD to 48 to 80mm
Full aperture frame
It holds up to four, 38mm lenses for each eye. Accessories may be easily inserted and extracted
Reduced aperture frame
Nosepiece for child. PD of 54 to 58mm and available for adults with PD 59 to 67mm
Half eye trial frame
Power is the SAME all throughout
Spherical lens
Convex
Plus
Concave
Minus
Thicker at the center thinner at the edge
Sphere Plus lenses (convex)
Made up of base-in prism
Sphere plus lenses
Converge rays of light
Sphere Plus lenses
CC lenses; thinner at center thicker at sides
Sphere minus lenses
Made up of base out prisms
Sphere minus lenses (concave)
Diverge rays of light
Sphere minus lenses
Could be minus or plus with axis markings
Cylinder
Surface has a flatter curve and and a greater curve
Cylinder
Used to measure and correct astigmatism
Cylinder lenses
Is a refractive medium having 2 plane surfaces inclined at an angle
Prism
Used to measure and correct the eye’s deviation from its normal plane
Prism
Used in dissociation tests
Prism
Comes in power range of 0.5 prism D, 1 PD to 6PD in 1P steps
Prism