Mod A Unit 4

Front 1

Transitions

Back 1

A brand name for lenses that turn dark when exposed to ultraviolet light

Front 2

Photochromatic

Back 2

The ability to change color when exposed to ultraviolet rays

Front 3

PGX

Back 3

A glass lens that can change color called photo grey extra

Front 4

PBX

Back 4

A glass lens that can change color called photo brown extra

Front 5

Silver halide crystals

Back 5

The glass ingredient that turns lenses dark

Front 6

Polarized lenses

Back 6

Thin laminated process to block light in one meridian and allow light through in the meridian 90 degrees away

Front 7

Presbyopia

Back 7

The crystalline lens loses its elasticity and a bifocal must be used to aid vision for near tasks

Front 8

G-15

Back 8

Dark green colored lens made popular by the military

Front 9

Anti-reflective coating

Back 9

Coating to reduce reflection and increase transmission

Front 10

Drop ball test

Back 10

Impact test for treated glass lenses

Front 11

Lens caliper

Back 11

Tool used to measure the thickness of a lens

Front 12

Heat treating

Back 12

Tempering process for glass lenses using heat to render them impact resistant

Front 13

Chemical tempering

Back 13

Tempering process for glass lenses using to render them impact resistant

Front 14

Colmascope

Back 14

Tool used to check if a glass lens has been safety tempered or is under stress

Front 15

Polariscope

Back 15

Same as colmascope

Front 16

Gradient lens tint

Back 16

Gradual change of darkening of the same color of tint on one lens

Front 17

Double gradient tint

Back 17

Gradual change from one color to another on the same lens

Front 18

Neutralizer

Back 18

Hot liquid to take out the tint color of a lens

Front 19

U.V. unit

Back 19

Hot U.V. liquid absorbed into the lens material

Front 20

Tinting unit

Back 20

Hot color tints absorbed into the lens material