Visual Impairment 5- Non Optical Aids Flashcards
(30 cards)
Whats classified as a non optical aid?
EVES TV/Computes/IPads Lighting Contra/colour Tints and glare Everyday living
What is the real image magnification?
Linear size if screen/linear size original objects
What are the advantages of EVES?
Rapid mag change Less tiring- binocular Flexible use psychologically accepted Enhanced contrast available Physical infirmity Reduced aberrations from high powered lens
What are the disadvantages of EVES?
Require practice Bulky Expensive Limited depth of focus Blur sensation of blur when text moves
In CCTV what helps reduce glare and flicker?
Reverse contrast
What are the advantages of P-EVES?
HAND HELD!! Psychologically accepted Rapid mag change Flexible use Less tiring Contrast reversal
What are the disadvantages of P-EVES?
MANNUAL DEXTERITY
LIMITED FOV- small screen
Requires flat surface
What is the best and preferred use if P-EVES?
Leisure reading increased length of time
Aid visual tasks
When can head mounted EVES be used?
Better for young patients and for better levels of acuity
…. although not widely used!
What would enhance reading speed?
Drifting text (PREFERRED) Rapid Serial Visual Presentations (RSVP)
What non optical aids can be used for reading?
Kindle
I pad
Monomouse
What adjustments were found to be made to computers to ease use?
Larger screens
Shorter viewing distance
Greater angular sizes
Assisstive technology
What were the benefits of using kindle?
Light weight Easy to handle No probs with stand mag 5x mag available Better congrats c LED screen
What is the contrast formula used?
Lmax-Lmin/Lmax+Lmin
What spectrum is most effected in VI pxs?
Red and blue spectrum
What areas in everyday living would need to have appropriate contrast and colour?
Stair/landing
Dangerous liquids
Electric sockets
Coloured plates
What 7 characteristics would improve good lighting?
- Appropriate for individual
- Tasks, orientation, movement
- Evenly spread c minim glare
- Adjustable
- Energy efficient
- Simple to install
- Adaptable for future
What are fall deaths contributed to?
Poor lightning and hip fractures (90,000 falls)
What is considered to be a better predictor of benefits of illumination?
Integrated contrast sensitivity
What should the patient be advised of in relation lighting?
Encourage for even illumination c supplemented task lighting
Why is luminance difference tiring?
If px has prolonged photostress recovery
What is the inverse square law?
Halfing the distance from light source will increase available illumination by 4x
What is the cosine law?
Increasing angle between object and light source will decrease available illumination
When should a tint be used?
If a condition is giving rise to VI
