Teaching the Use of Magnifiers for Reading

The following paper was presented by Marion Blazé (Visiting Teacher for Vision Impaired, Catholic Education Office, Victoria) at the Term III conference at the Statewide Vision Resource Centre, 11 August 2000.

Visiting (Itinerant) Teachers have all observed huge variation between skills of vision impaired students who use magnifiers. There are many non-users, some refusers, those who use them for reading labels and diagrams only and some who read everything with them. I knew one senior student who ‘wore’ his magnifier in his eye socket and used it to read everything!

So, why should students use magnifiers?

Disadvantages for users of large print

Advantages for users of large print

Disadvantages for users of magnifiers

Advantages of magnifiers

I believe these last two points make the teaching of efficient magnifier use essential for many of our students. Magnifiers offer our students more independence and options for literacy at and after school.

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What does research tell us about the efficiency of using magnifiers or large print?

Prescription of magnifiers by an optometrist

For students with vision impairments, magnifiers should ALWAYS be prescribed by an optometrist as there are many optical considerations to be assessed to optimise the student’s visual functioning. If a magnification device is prescribed for your student, there are a number of details which need to be asked of the optometrist.

These include:

Focal distance chart

This should be used as a guide to the correct use of a magnifier.

Reference: Foundations of Low Vision pp.129

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The “mechanics” of reading with a magnifier

It is important to ensure that the mechanics of reading with a magnifier are explained to the student. The first consideration is the ‘perceptual span’. The idea is to get the required magnification with the widest field of view or ‘perceptual span’. Reading rate is directly influenced by the width of the perceptual span in reading. The typical perceptual span of a mature reader is 7 to 10 letters, i.e. amount of information the individual can decode and store in short-term memory in one fixation, before going on to next piece of information. A typical length of a saccade (the movement of the eye between fixations on the print) is 5 to 7 words or the width of newspaper columns. Students will often start reading with their eyes some distance from the magnifier, until they realise that with the eye closer to magnifier, their perceptual span widens. The student needs to be taught how to widen their perceptual span, i.e. get their eye/s closer to the magnifier.

If the optometrist prescribes a magnifier to be used with spectacles, we need to ask if, for sustained reading it can be used without spectacles to decrease the distance from the eye to the magnifier.

Eye-hand coordination is another important skill for a magnifier reader and is one of the reasons that magnifiers are not often prescribed to children below about year 3. (The other reason being that young children can accommodate so close that they often get sufficient magnification from bringing the print very close.) Movement of an unsteady hand is ‘magnified’ on the page. The magnifier lens must remain parallel to the page. Any tilt will exaggerate lens aberrations. This may not be immediately apparent to a student with low vision.

Another important skill involves tracking and eye movements. Efficient, mature readers utilise smooth, rightward saccades with few regressions. Low vision readers using magnifiers have been found to adopt ‘saw-tooth’ eye movements. These are caused by the eye following the apparent leftward movement of the print as the magnifier is moved to the right. The ‘saw-tooth’ movement lowers reading speed and comprehension and increases fatigue (Fotinakis & Dickinson, 1994). Any training must attempt to minimise this. Also, the velocity of smooth eye movements must be well matched to that of the moving letters under the magnifier, otherwise comprehension is lost.

Lighting must also be considered. The magnifier may occlude light so the student must be made aware of where to position himself in relation to light when using the magnifier.

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The teaching of reading with a magnifier

Positive modelling is often neglected for students with vision impairments because they are invariably the only student with vision problems in their school. Students need the opportunity to meet with and observe proficient readers with magnifiers. It is difficult to be confident about mastering a new skill if you’ve never known anyone else capable of it.

I stress again the importance of teaching the student about the mechanics of reading with a magnifier. Students must understand how to find the focal distance and how to vary their perceptual span. One optometrist suggests attaching a piece of string to the magnifier with a knot to indicate how far it should be held from the page. The student should also understand the implications of and the need for smooth, rightward eye movements. You should also explain that initially reading may be slower as the student concentrates on use of the device rather than the reading task.

Should the student move the page or move the magnifier and eyes? This depends on the task and the type of material. It is OK to move a single page flat on a table top or reading stand. This becomes a bit too difficult with books.

The student will need to do some reading exercises with the magnifier to build up their skills. I would not recommend isolated letter or word exercises as the student should be trying to maximise his/her perceptual span.

Start with the print size recommended by the optometrist. Try larger print if the student is not coping, or go smaller if s/he is coping well. The student should be able to reduce the initial print size with practice.

The first exercise should comprise short phrases, well spaced between columns and lines. (See reading exercise charts.) The student can start with one column, moving to several columns, practicing smooth rightward movements. We should always try to spark the interest of our students. Make up phrases which will amuse, take phrases from a favourite book or pick a pet topic e.g. football.

If the student has difficulty tracking, use an ‘aperture’ - a piece of cardboard which occludes all but one line of print. First use a black aperture on white paper, then grey, then a fine line under the print, then a ‘white’ mask so the student is reading only one line. (Use white cardboard on the white page to occlude all but the one line without giving a contrasting aperture.) This will move the student away from concentrating on the aperture for tracking, and onto tracking the line of print.

Use a pointer at the beginning of the line, if movement from one line to the next causes difficulties.

Move to columns of text (of interest to the student). For this, one can use magazine articles about footy stars, kids magazines articles or any short, factual, interesting stories. Again use ‘apertures’, if needed. Aim not to use these permanently as the magnifier is enough to handle.

Finally, move to normal reading materials. Hard backs are easier than paper backs as the student needs to sit the book flat and paper backs don’t open absolutely flat. As manual skills increase, give the student a specific purpose for reading (e.g. find out answer to question) so that his/her focus moves away from the magnifier and onto the reading task.

Ideas for Encouraging Reading with a Magnifier 
See Reading Exercise Chart - three examples 
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Increasing reading speeds

Typical reading rates for mature readers - oral and silent reading rates (in words per minute)

Reference: Foundations of Low Vision pp.259

Reading rates for people with low vision (in words for minute)

Reference: Foundations of Low Vision pp.284

Teachers often believe that low reading rates are a natural outcome of having low vision and hence do not attempt to provide training to improve skills. Suggesting that the low vision student does every second question or reads fewer books because of time limits, whilst often practical, perpetuates the low vision student’s poor skills and stamina and disadvantage in exposure to reading. Good readers become so through reading!

Strategies for increasing reading fluency and speed

Reference: Corn & Koenig, 1996

Repeated readings:

Paired reading:

Choral reading:

Echo reading:

Fatigue

Vision impaired students should be taught to recognise the signs of both visual and postural fatigue. Offer the student strategies to deal with them. For example:

The student may also try relaxation techniques. “Imagine a knot behind your eyes, close eyes and imagine the knot gradually untying, think of a peaceful place, ..........”

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Graphics

Tables are great to read with magnifiers because they are just like reading columns. The student may need to revert to the use of an ‘aperture’ if there are long gaps between columns. Ensure that the student is aware of the labelling conventions of tables.

For graphs, the student needs to look at it without the magnifier first. Although the student won’t see detail, s/he can see the overall shape of the graph. If you use a photocopy of graphs in books, the teacher can circle specific parts to teach certain concepts. Again, the student may need an ‘aperture’ to track to points. Also, as with tables, ensure that the student understands the conventions of labels on graphs. There are some good mainstream books available to teach graphing skills. Use these as part of your student’s magnifier training, if the student requires this.

For pictures and diagrams, again it helps to look at diagrams without the magnifier first. Diagrams are difficult to perceptualise in small chunks and there are few conventions to rely on. The student’s instructions may need to be specific to individual diagrams. For example, instruct the student to use the key, read labels and follow arrows to diagram part, whether the diagram is shown with or without perspective.

The beauty of using a magnifier with diagrams is that the student can use the colour copy instead of a black & white enlargement.

What to tell teachers when your student reads with a magnifier

Teachers should be told to expect a slower reading speed (at least initially!). It is helpful if they are made aware of some of the mechanics such as the fixed focal distance and that a close reading distance OK and often necessary when using the aid.

Teachers need to know that, whilst the aid will solve many problems it may create a few, too. Visual and postural fatigue may be increased at least in the early stages of using the magnifier. The student’s field of view will be reduced by the aid. This is especially important when viewing graphics.

Conclusion

Although there are some disadvantages to using a magnifier and students need to commit to some training and practice, their independence and options for reading will be unlimited if the skill is attained. This skill will remain with them beyond their school years when large print will be much more difficult to obtain.

References

Corn, A., Optical Devices or Large-Type: is there a debate? Paper presented at International Conference on Low Vision, 1990

Corn, A. & Koenig, A. Ed., Foundations of Low Vision: Clinical & functional perspectives, AFB Press, New York, 1996.

Fotinakis, V. & Dickinson, C., ‘Reading with magnifiers’ in Low Vision - Research & new developments in rehabilitation by Kooijman, Looijestijn, Welling 7 Wildt, IOS Press, Netherlands, 1994.

Spitzberg, L., Goodrich, G. & Perez-Franco, A. ‘Reading with vertical magnification with Retinitis Pigmentosa’ in Low Vision - Research & new developments in rehabilitation by Kooijman, Looijestijn, Welling 7 Wildt, IOS Press, Netherlands, 1994.

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