2Introduction Over a billion people worldwide need glasses By using self-adjustable glasses almost anyone can provide glassesYou are here to learn how to do this!
3What you will learn The causes of poor vision How to check for poor distance and close visionWhat sort of glasses will fix different types of poor visionHow to provide self-adjustable glassesWhen you can’t help someone
4What causes poor vision? In this section, you will learn:Why we see and the parts of the human eyeWhat refractive error isThe types of refractive errorHow to treat refractive error with glassesSome diseases that can cause poor vision
6Refractive Error Normal eye (Emmetropia) Short-sightedness (Myopia) Long-sightedness(Hyperopia)
7PresbyopiaBy the age of 45-50, most people have trouble accommodating (changing the lens shape to focus on near objects)To help the eye see close objects, we must add positive power (use positive glasses lenses)People with long-sightedness find it more difficult to see distant objects as they get older because of presbyopia
8Other problems Astigmatism – a type of refractive error Cataracts Pinguecula and PterygiumConjunctivitisTrachomaOther eye diseasesMacular degenerationRetinitis PigmentosaRetinopathyGlaucomaSquint or strabismus
9How to do a sight test In this section, you will learn: What to do before you startThe TestHow to do a distance vision testHow to do a near vision testThe best way to record information
10Before you startYou must not give self-adjustable glasses to people under 14 years old or are too small to fit.You should find out where the nearest eye hospital or eyecare professional is, and refer people with eye problems you cannot help with to there.If the person is sick, has an eye infection or their eyes are watering, they should not be tested.
11Local knowledgeYou should be fluent enough, or have people fluent enough, in the local language to communicate about the sight test and adjusting the lensesLearn how to explain:“Don’t squint”“We can’t help you”“You should adjust the lenses until the world becomes clear”Older people are often more difficult to examine
12Required Equipment You must have the following: A Distance Vision ChartA Close Vision ChartThese items are optional but can help in the near vision test:A book or magazine ORUseful items for near vision tasks (such as a needle and thread). This is for people who cannot read.
16The TestPoint to a single letter on each line. Keep moving down the chart until the person gets ONE letter wrong.Then move TWO lines up the chart and point to every letter on the line.Keep pointing to every letter on the line, moving down the chart, until the person gets TWO letters wrong on one line. Then stop.Record the line number ONE above where you stop.
17Distance Vision Test Check if the person should be tested People who wear glasses should be tested with their glasses onDo the Test with the distance vision chartIf the person cannot see line 7 with one eye, they might need glasses to help with distance vision
18Near Vision TestCan the person see distance clearly (with or without any new glasses you have provided)?Do the Test with the near vision chartORCheck that they can do near tasks, such as readingIf they cannot see line 7 with one eye or cannot do near vision tasks, they should try glasses for near vision
19How to provide glasses In this section, you will learn: About EyejustersHow to choose and adjust glasses for distance visionHow to choose and adjust glasses for near visionRecording information about the adjusted glassesHow to care for the glassesFinal things you have to do before you provide glasses
20Things to rememberIf a person does not pass the distance vision test, they may need glasses for distance visionIf after attempting to fit and adjust glasses for distance vision, the person’s distance vision has not improved, you should stop the sight test and advise them to visit an eye doctor.If a person does not pass the near vision test, they will need glasses for near vision.If they are over 45, they will probably need glasses for near vision.A person may need glasses for both distance and near vision.
22Types of EyejustersPositive Power: used by people with long-sightedness (hyperopia) who need distance glasses, and those who need glasses for near vision.Negative Power: used by people with short-sightedness (myopia) who need distance glasses.
24Adjusting the glassesClip the magnetic adjuster dial into the adjuster holePut the glasses on.Cover the eye you are not adjusting with your hand.Rotate the adjuster dial all the way forward.Rotate the adjuster dial slowly until you can see clearly, then fine-tune the adjustment.Remove the adjuster dial by gently pulling it out of the adjuster hole.Repeat for the other lens.
25Fitting glasses for distance vision Pick the right glasses (see table or start with negative glasses)Introduce the glassesFollow the adjusting procedure (previous slide)Re-testCheck fit and comfort
26Fitting glasses for near vision Pick the right glasses (see the table or start with positive glasses)If you have reading glasses, pick the right powerIntroduce the glassesFollow the adjusting procedure (on a previous slide)Re-testCheck fit and comfort
27Checking the fitMake sure user is looking through the middle of the lensGentle pressure can be applied to side-arms, nose pads and nose bridge to change the shape and fit of the frame for comfort
28Providing the glasses Explain about the ‘break-in’ period Check fit and comfortCheck cleaning cloth and instructions are in caseExplain how to look after the glasses, including how to open the lenses to clean inside themMake sure you record information on your sheet