Reading should not leave you wanting to close one eye. If close work brings on tired eyes, blur or double vision, the way your eyes work together may need checking—even when you can read the eye chart clearly. 1 At Vision Camberwell Optometrists, we assess binocular vision and focusing problems and help with complex prism prescriptions.
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Sudden double vision needs urgent assessment
If double vision starts suddenly, or comes with eye pain, seek urgent medical assessment today. Double vision after a head injury, or with a severe headache or an enlarged pupil, needs immediate emergency assessment. Do not wait for a routine appointment. 2
What is a binocular vision problem?
Binocular vision is how your two eyes work together. Convergence is the inward movement needed for close work. With convergence insufficiency, maintaining that alignment is difficult, so nearby objects may blur or appear double. 1
Focusing and eye alignment are related, but different
Accommodation is your eye’s ability to adjust focus for near tasks. Accommodative insufficiency means that focusing ability is lower than expected for your age. It can make sustained close work uncomfortable and may occur alongside an eye coordination problem. Checking both helps guide treatment. 3
Double vision has more than one possible cause
Some double vision relates to eye alignment; other causes affect the image seen through one eye. Whether the doubling disappears when either eye is covered is useful information for your clinician, but it does not replace an examination. The cause determines the treatment and whether referral is needed. 2
When should you book a binocular vision assessment?
Recurring headaches, tired eyes, blur or double vision during reading and screen use are reasons to arrange an assessment. A child may rub their eyes or close one eye during close work. 1 Tell us what you notice, when it happens and whether it is changing.
These symptoms do not establish a diagnosis on their own. We want to understand what is making the task difficult before recommending glasses, prism or exercises. If your concern is reading progress, tell us about that too, so eye care can sit alongside the other support your child may need.
What happens during the assessment?
We start with your symptoms and everyday tasks
Tell us whether the difficulty occurs at a computer, with a book, when looking into the distance, or when changing between tasks. Bring your current prescription and explain what your existing glasses help with—and what they do not. Previous eye surgery, injuries and medical care are also useful parts of the history.
We check eye coordination and focusing
Testing may assess alignment at near and distance, how close a target can move before the eyes lose alignment, and how well focus changes between distances. 1 Focusing measurements are considered alongside your prescription and eye health, rather than treated as a stand-alone explanation for every symptom. 3
We explain the findings and the next step
We will talk through whether the findings fit your symptoms and what the options mean for you. Depending on the cause, the next step may involve a prescription change, a prism trial, a structured exercise programme or referral for further assessment. We will explain where any recommended care will take place.
How are binocular vision and focusing problems treated?
Glasses and focusing support
An appropriate glasses prescription is part of managing a focusing problem. Some people with accommodative insufficiency may benefit from additional near correction or prescribed exercises. The evidence does not establish one best treatment for everyone, so recommendations need to reflect the diagnosis and response to care. 3
Exercises for convergence insufficiency
For children with symptomatic convergence insufficiency, a Cochrane review found strong evidence that supervised office-based vergence and accommodative therapy, reinforced at home, improved convergence more than home pencil push-ups or home computer therapy. 4
That does not mean everyone with eye strain needs a course of vision therapy. Treatment should follow a confirmed diagnosis, with agreed goals and review. We will discuss whether exercises are appropriate and whether another provider needs to be involved.
Prism glasses for selected alignment problems
Prism changes the direction of light entering the eyes to help bring two images together. It can help selected people with double vision caused by misalignment. It does not treat every cause of double vision, and the underlying cause still needs assessment. 5
Prism is not an interchangeable substitute for exercises in every convergence insufficiency case. In the Cochrane review, one trial in children found no advantage of prism reading glasses over placebo glasses. One adult trial found symptom improvement without improved convergence measurements. These findings concern this particular condition and do not rule out prism for other diagnosed alignment problems. 4
Help with complex prism prescriptions
If you have been told your prism prescription is difficult to manufacture, bring it to us. Shonit Jagmohan handles VCO’s complex prism cases, including prescriptions that need discussion beyond a standard lens order.
For suitable complex prescriptions, we source spectacle lenses from laboratories in Sweden and the United States. We assess the prescription and check what can be made before recommending a lens. Availability, frame suitability, cost and delivery time need to be confirmed for the individual order.
Fresnel and ground-in prism lenses
A Fresnel prism is a thin plastic prism fitted to a spectacle lens. It can be useful for a trial and can cause some blur in the eye looking through it. 6 A ground-in prism is incorporated into the spectacle lens itself. It may be considered once an appropriate prescription has been established. 5
The aim is a workable correction for your particular needs. A press-on prism is not a failed result, and a ground-in lens is not automatically the right choice. We will explain the available options before you commit to new lenses.
Before your appointment
Bring your current glasses, including any prism or reading pairs, your latest prescription and any relevant ophthalmology or orthoptic reports. If you have tried exercises or a Fresnel prism, tell us what was prescribed and how you found it.
It helps to note when symptoms start, which tasks bring them on and how long they last. If the appointment is for your child, bring any observations from home or school. See also our children’s eye tests page. Mention a complex prism prescription when booking so we can direct the enquiry appropriately.
Binocular vision care in Camberwell
Vision Camberwell Optometrists is at 784 Burke Road, Camberwell VIC 3124, in Melbourne’s inner east. We welcome patients from Camberwell, Hawthorn, Balwyn, Kew, Canterbury and across Melbourne. Binocular vision testing can be arranged alongside a comprehensive eye test, and forms part of our wider eye care services.
For English or Mandarin consultations, ask about an appointment with Jue Wang. For complex prism enquiries, let our team know when you contact us so we can arrange the appropriate clinician.
To arrange an assessment, call (03) 9882 5666 or contact our team. Tell us about any double vision when booking; sudden symptoms require urgent assessment as described above.
Questions about binocular vision and prism glasses
Can I have a binocular vision problem if my eyesight is clear?
Yes. Clear eye-chart vision does not rule out convergence insufficiency. Eye coordination needs its own assessment when symptoms suggest a problem. 1
Do I need prism glasses for eye strain?
Not necessarily. Prism helps selected alignment problems, and eye strain alone is not enough to decide that you need it. The assessment should establish the cause and whether a prism trial is appropriate. 5
Will vision therapy improve my child’s reading?
It should not be promised as a reading treatment. In the CITT-ART randomised trial, 16 weeks of vergence and accommodative therapy did not improve standardised reading outcomes more than placebo therapy in children with convergence insufficiency. Treating an identified eye problem does not replace appropriate assessment and support for reading difficulties. 7
Can you help if my prism prescription is difficult to make?
We can review the prescription and explore manufacturing options, including our laboratory contacts in Sweden and the United States. We need to confirm feasibility for your particular prescription before promising that a lens can be supplied.
Is sudden double vision an emergency?
Sudden double vision needs urgent medical assessment, even if it comes and goes. Go to an emergency department immediately if it follows a head injury or occurs with a severe headache or an enlarged pupil. 2
References
- National Eye Institute. Convergence Insufficiency. National Institutes of Health. Patient information. Accessed 14 September 2026.
- NHS. Double vision. Patient guidance. Accessed 14 September 2026.
- Hussaindeen JR, Murali A. Accommodative Insufficiency: Prevalence, Impact and Treatment Options. Clinical Optometry. 2020;12:135–149. doi:10.2147/OPTO.S224216.
- Scheiman M, Kulp MT, Cotter SA, Lawrenson JG, Wang L, Li T. Interventions for convergence insufficiency: a network meta-analysis. Cochrane Database of Systematic Reviews. 2020;12:CD006768. doi:10.1002/14651858.CD006768.pub3.
- American Academy of Ophthalmology. What Is Prism Correction in Eyeglasses?. Patient information. Published 23 April 2023.
- Cambridge University Hospitals NHS Foundation Trust. How to fit a Fresnel Prism. Patient information. Accessed 14 September 2026.
- CITT-ART Investigator Group. Effect of Vergence/Accommodative Therapy on Reading in Children with Convergence Insufficiency: A Randomized Clinical Trial. Optometry and Vision Science. 2019;96(11):836–849. doi:10.1097/OPX.0000000000001442.
Reviewed by Dr Shonit Jagmohan, B.Optom (Hons), FIAOMC, IACMM, Ophthalmic Medicines Prescriber, Fellowship Chair for the International Academy of Orthokeratology and Myopia Control (Oceania). Last reviewed October 2026.
Visit us in Camberwell
T. (03) 9882 5666
E. vision@visioncamberwell.com.au
Find Us at:
784 Burke Rd, Camberwell
Victoria 3124, Australia
Opening Hours:
Monday, Tuesday and Friday. 9am – 6pm
Wednesday. 9am – 5pm
Thursday. 10.30am – 7.30pm
Saturday. CLOSED
Book your appointment with one of our friendly team members today
T: (03) 9882 5666
Serving Camberwell and the Surrounding South Eastern Suburbs
An independent practice in Camberwell since 1951, we are experts in binocular vision assessments and complex prism prescriptions. We welcome patients from Hawthorn, Deepdene, Surrey Hills, Balwyn, Kew, Canterbury, Box Hill, Glen Iris, and across greater Melbourne.
