Eye Zen
眼静
Prism Glasses for Double Vision in Singapore
Understanding Prism Glasses for Double Vision
Prism glasses may be prescribed for certain people experiencing double vision (diplopia), eye alignment difficulties or binocular vision problems.
However, prism spectacles are not simply about adding prism to a prescription. Comfort and visual performance can also depend on the underlying visual condition, the amount and direction of prism required, the spectacle prescription, lens design, accurate measurements and how the finished spectacles sit in front of the eyes.
At Eye Zen Optical Singapore, we take a personalised approach to prism spectacle requirements, particularly for customers with double vision, binocular vision difficulties and complex spectacle prescriptions.
Who May Need Prism Glasses?
Prism glasses may be considered when the two eyes have difficulty working together comfortably and a prism prescription has been recommended as part of the person's visual correction.
People seeking prism spectacles may experience symptoms such as:
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Double vision
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Images appearing separated or displaced
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Eye strain or visual fatigue
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Headaches associated with visual tasks
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Difficulty keeping vision comfortable for prolonged periods
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Difficulty reading or concentrating on near work
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Visual discomfort when looking at certain distances
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Difficulty adapting to an existing spectacle prescription
The presence of these symptoms does not automatically mean prism glasses are required. Similar symptoms can occur for many different reasons, so the underlying visual problem should first be appropriately assessed.
Prism Glasses and Double Vision
Double vision, also known as diplopia, means seeing two images of a single object.
For some people with binocular double vision, prism may form part of the spectacle prescription to help provide more comfortable single vision.
Whether prism is appropriate depends on factors including the cause and pattern of the double vision, whether it is constant or intermittent, the direction of the image separation and the person's overall binocular vision.
Not every case of double vision should be managed with prism spectacles.
Sudden or unexplained new double vision requires prompt medical assessment, particularly when accompanied by other neurological, eye or general health symptoms.
Prism Glasses and Binocular Vision Problems
Binocular vision refers to the ability of both eyes to work together as a coordinated pair.
Some people have difficulty maintaining comfortable binocular vision even when each eye can see clearly individually.
Depending on the individual condition and professional assessment, prism may sometimes be prescribed for binocular vision difficulties associated with conditions such as:
A phoria is a tendency for the eyes to drift from their normal alignment when binocular fusion is interrupted.
Many people have a small phoria without symptoms. In some cases, however, difficulty compensating for an eye alignment tendency may contribute to eye strain, headaches, visual fatigue or intermittent double vision.
Prism may be considered in selected cases when clinically appropriate.
Strabismus is a manifest eye misalignment in which the eyes are not consistently directed towards the same target.
Some people with strabismus experience double vision, while others do not.
Prism spectacles may be useful for certain individuals experiencing double vision associated with eye misalignment, but they are not appropriate for every type or degree of strabismus.
Prism spectacles should also not be assumed to physically straighten the eyes or treat the underlying cause of strabismus.
Horizontal and Vertical Prism Requirements
Not all prism prescriptions are the same.
Some people require correction related predominantly to horizontal image separation, while others may experience vertical image separation. More complex cases can involve a combination of directions.
This is one reason why prism spectacles should not be approached as a standard spectacle prescription.
The direction and amount prescribed need to correspond with the individual's visual requirements, and the finished spectacles must be produced and positioned accurately.
Why Accurate Spectacle Measurements Matter
With complex spectacle prescriptions, good vision depends on more than the prescription written on paper.
Factors that may influence the comfort and performance of prism spectacles include:
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Pupillary measurements
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Optical centration
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Lens positioning
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Frame size and shape
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Frame adjustment
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Vertex distance
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Pantoscopic tilt
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Face-form angle
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Prescription strength
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Differences in prescription between the two eyes
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Previous spectacle and prism experience
These factors become particularly important when prism is combined with higher prescriptions, anisometropia or progressive lenses.
At Eye Zen Optical, we consider how the complete spectacle system works together rather than looking at the prism value in isolation.
Prism Glasses with Different Prescriptions Between the Eyes
Some people requiring prism also have significantly different prescriptions between their two eyes, known as anisometropia.
This can make spectacle correction more complex because each eye may experience a different optical effect through its lens.
The combination of anisometropia, binocular vision difficulties and prism requirements may therefore require additional consideration of:
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Prescription balance
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Lens design
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Lens thickness and material
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Optical centration
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Frame selection
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Previous spectacle experience
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Visual comfort at different viewing distances
For customers with complex prescriptions, these details can be important when trying to achieve comfortable spectacle wear.
Can Prism Be Included in Progressive Lenses?
In suitable cases, a prism prescription may be incorporated into progressive spectacles.
However, progressive lenses already require accurate fitting because the wearer uses different areas of the lens for distance, intermediate and near vision.
When prism requirements and progressive correction are combined, factors such as prescription, binocular vision, progressive lens design, monocular pupillary measurements, fitting height and frame position become particularly important.
For someone who has previously struggled with progressive lenses, simply changing to another progressive lens without understanding the source of the discomfort may not address the problem.
At Eye Zen Optical, we look at the complete prescription and fitting relationship, especially when progressive-lens discomfort exists together with binocular vision or prism requirements.
Why Do My New Prism Glasses Feel Different?
A new prism prescription may feel different from ordinary spectacles, particularly during the initial adaptation period.
Some people may notice temporary changes in:
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Spatial perception
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Visual orientation
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Eye coordination
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Reading comfort
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Distance judgement
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General awareness of their new spectacles
The amount of adaptation varies between individuals.
However, persistent double vision, significant dizziness, headaches or substantial visual discomfort should not automatically be dismissed as something you simply have to “get used to.”
The prescription, spectacle measurements, lens positioning and frame fitting may need to be reviewed.
Why Were My Old Prism Glasses More Comfortable?
Sometimes a person receives a new pair of spectacles based on a current prescription but finds that the older pair still feels more comfortable.
There can be several reasons.
The difference may involve the prism prescription itself, changes in the underlying visual condition, the spectacle prescription, lens design, optical centration, frame geometry or the position of the lenses in front of the eyes.
Previous adaptation also matters.
When troubleshooting uncomfortable prism spectacles, comparing the old and new spectacles can provide useful information.
If possible, bring your previous comfortable spectacles with you when visiting Eye Zen Optical.
Does Needing Prism Mean My Eyes Are Getting Worse?
Not necessarily.
A prism requirement by itself does not explain why a person's vision has changed or whether an underlying condition is progressing.
Changes in double vision or binocular vision can occur for different reasons, and the appropriate response depends on the individual situation.
If double vision is new, sudden, unexplained or changing significantly, medical assessment may be necessary before considering spectacle solutions.
Can Prism Glasses Cure Double Vision?
Prism glasses should not be described as a universal cure for double vision.
For selected people, an appropriate prism prescription may help provide more comfortable single vision or reduce symptoms associated with a particular binocular vision problem.
The result depends on the underlying cause, stability of the condition, visual requirements and individual response.
Some forms of double vision require medical investigation or other forms of management rather than, or in addition to, spectacle correction.
When Should Double Vision Be Medically Assessed?
Double vision can sometimes be associated with conditions that require medical investigation.
Seek prompt medical attention for new or sudden double vision, particularly if it occurs together with symptoms such as:
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Sudden vision loss
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Severe or unusual headache
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Drooping eyelid
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Weakness or numbness
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Difficulty speaking
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Loss of balance
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Eye pain
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Recent head injury
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Other sudden neurological symptoms
Optical management should not delay appropriate medical assessment.
Eye Zen Optical's Approach to Prism Spectacles
At Eye Zen Optical, our approach starts with understanding the person behind the prescription.
We consider:
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The visual symptoms you are experiencing
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When and where the symptoms occur
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Your current prism and spectacle prescription
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Previous prescriptions
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Your existing spectacles
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Your binocular vision requirements
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Differences between the prescriptions of your two eyes
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Lens design
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Accurate spectacle measurements
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Frame selection and adjustment
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Distance, intermediate and near visual requirements
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Previous adaptation difficulties
For customers who already have prism spectacles but remain uncomfortable, we also look for differences between the existing spectacles and previous pairs that were more successful.
The objective is not simply to make a pair of spectacles containing prism. It is to provide a carefully considered spectacle solution based on the individual's prescription, visual requirements and previous experience.
About Allen
Allen is the founder and optician at Eye Zen Optical in Singapore.
He has worked in opticianry since 2005 and has a particular interest in personalised spectacle solutions for customers with complex visual requirements, including double vision, binocular vision difficulties, prism prescriptions, anisometropia and progressive-lens discomfort.
His approach considers not only the written prescription but also lens selection, spectacle measurements, frame fitting, previous spectacle experience and the customer's day-to-day visual requirements.
Frequently Asked Questions About Prism Glasses
Are prism glasses only for double vision?
No. Prism may be prescribed for different binocular vision and eye-alignment requirements. Whether it is appropriate depends on the individual's visual condition and professional assessment.
Can prism glasses help all types of double vision?
No. The suitability of prism depends on the cause and characteristics of the double vision. Some cases require medical investigation or other forms of management.
Can prism be used in progressive lenses?
In suitable cases, yes. Combining prism with progressive correction requires careful consideration of the prescription, progressive lens design, measurements, fitting and binocular visual requirements.
Why am I still seeing double with my prism glasses?
There can be several possible reasons, including changes in the visual condition, prescription requirements, spectacle positioning or other factors. Persistent or changing double vision should be appropriately reassessed.
Should I bring my old prism glasses?
Yes. If you have previous spectacles—especially a pair that was comfortable—bring them with you. Comparing previous and current spectacles can provide useful information when investigating visual discomfort.
Do prism glasses straighten the eyes?
Prism spectacles should not be assumed to physically straighten an eye. They may be prescribed to help manage certain visual symptoms or binocular vision requirements.
Will I need prism glasses permanently?
Not necessarily. Prism requirements vary depending on the underlying condition and whether it remains stable or changes over time. Your requirements should be reviewed when appropriate.
Personalised Prism Spectacle Solutions in Singapore
If you have been prescribed prism, experience double vision, have difficulty adapting to your current prism spectacles or have a complex prescription involving binocular vision or progressive lenses, Eye Zen Optical can review your spectacle requirements and discuss appropriate optical options.
Eye Zen Optical
71 Kallang Bahru #01-529D
Singapore 330071
WhatsApp / Call: +65 8048 8379
Book a consultation with Eye Zen Optical to discuss your visual concerns.