Dispensing in Sport Flashcards
1
Q
Sports Eyewear aims to:
A
1) Imporove vision
- enhance contrast
- reduce glare
2) Provide protection
- impact resistance
- UV protection
2
Q
Different types of sports glasses
A
-racquet
-snooker glasses
-shooting glasses
-ski goggles
-swimming goggles
-diving mask
cycling/running
3
Q
What sorts of problems does blunt trauma cause?
A
- blow out fracture
- ruptured globe
- hyphema
- retinal haemorrage
- retinal detachment
- commotio retinae
4
Q
Raquet sports glasses - things to consider
A
- squash ball travels at high velocity - can be as high as 176 mph
- squash ball is approx 40mm diameter
- injuries due to raquet sports represent 47.5% of ocular trauma that required hospital admission
- frames and lenses need to provide protection
- must conform to EN167 and EN16 (personal eye protection) Squash - BS7930:1
- now mandatory for all doubles squash players and juniors to wear protective eyewear
- can be glazed with rx - would be limited supply
- glazed loose to allow impact to be absorbed by glasses
- cant be worn over pxs own glasses
5
Q
Frames and lenses for raquet glasses
A
Frames:
- thick silicone moulded cushion pads to protect the nose on impact
- elasticated headbands instead of standard sides
- can be ventilated to prevent steaming up
- should be adjustable for good fit
- commonly nylon
Lenses:
- polycarbonate for impact resistance
- coated for anti fog
- can be high base curve if curved - the more they’re curved the higher the base curve required
6
Q
Snooker Glasses
A
Things to consider:
- head position - needs retroscopic tilt, body is at 90 degrees usually chin up and looking right through top of glasses
- effect on vision - need to take into consideration for tca
Frames
- must have joint angles to allow for retro and panto tilt
- dispensers rule for retro tilt - raise heights by half
Lenses
- require 50mm depth
- MAR
- the visual axes must still be approx normal to the lens
7
Q
Shooting glasses
A
Things to consider: eye dominance and contrast
Lenses
- lenses can be tilted and centered according to the shooters position
- the non shooting eye can be occluded
- a lighter tint may be better for shooting as the pupils behind a darker tint will dilate and so will allow more light in and increase aberrations
- need uv coating as theyre more likely to be outside
Frames:
- can be hung from a mount
- can include a pinhole
8
Q
Skiing goggles
A
Things to consider:
- uv because of snow reflecting BS EN 12312
- impact resistance
- tints
- prescription
- not polarising as you wnat the light to be reflected off the bumps so they can manouevre around them
Frames
- often have removable insert for glazing - dont need to worry about a steep base curve, and if rx changes insert can be sent away and reglazed
- adjustable headband
Lenses
- grey tint
- yellow/rose tints - help to filter out blue light, more clarity
- mirror coatings
- polycarbonate/trivex
- anti fog
9
Q
Swimming goggles
A
- remember the lens equation
- as were not in air n=1.333 - so power of lens is 1/3 of that in air
- we glaze plano concave/convex on front surface and not as meniscus so we dont need to worry about alteration when px is in water
- highest rx in swimming goggles is +6DS -not good for people with high cyl
- shouldnt wear lenses in water - can get eye infections
10
Q
Diving masks
A
Things to consider
- pressure changes
- prescription
- watertight fit
Frame
- can be full or half mask
- silicone seal
Lenses
- should be tempered glass
- can have rx insert
11
Q
Cycling/running
A
Points to consider
- impact resistance
- smaller debris - dust, insects
- uv protection
- glare protection
- fov
- contrast enhancement
Frames
- require excellent fit
- lightweight
- detachable sides
- interchangeable lenses
Lenses
- polycarbonate for impact resistance
- wrapped - so consider base curve to increase FOV and off axis performance
- contrast enhancing tints
