View the answers to our most frequently asked questions:
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FAQ`s
General Queries
Why is an eye examination so important?
Your eyes are precious and need to be taken care of. Regular eye examinations will ensure that both the health of your eyes and your vision can be monitored and any problems detected at an early stage.
How often should I have a Sight Test?
At HBD we recommend that you have your eyes examined at least every 2 years. Certain medical conditions require monitoring on a regular basis, and yearly examinations are recommended in these cases. Should you wear contact lenses, yearly appointments are obligatory to renew your annual contact lens prescription. These recommended intervals assume that you are not experiencing any discomfort or visual change.
Will my sight deteriorate if I start wearing Spectacles or Contact Lenses?
Wearing a prescription does not make your vision deteriorate. When putting on your spectacles for the first time, you may be surprised at the sharpness of the detail you are seeing – this is because the retinal image is now perfectly focused on your retina and your brain is able to interpret this as a high definition mental picture. Objects were seen with this clarity previously until the change in your prescription brought about a ‘soft focus’ to your vision. Removal of your spectacles can give you the impression that your vision has got worse, when in fact your brain is now in a position to compare the high definition picture through your spectacles with the previously soft uncorrected picture without. Both nature (your genes) and nurture (life’s influence on you) will play a part in how your eyes change with time.
What does the eye examination involve?
By carefully interpreting any symptoms or history you may have, an Optometrist is able to carry out a series of examinations and measurements to determine your optimal prescription and general health of your eyes. Should it prove necessary, further equipment may be used to assess your eye pressures, visual fields, colour vision status. Retinal Photography allows detailed examination of your retinas, and provides a permanent record for future reference.
What is the difference between 20/20 and 6/6 vision?
No difference! Both these fractions denote perfect sight. 20/20 is the imperial version measured in feet whilst 6/6 is the metric equivalent measured in metres.
Driving Related Questions
What is the legal vision requirement for driving?
You must be able to read a standard number plate on a motor vehicle, in good light, from a distance of 20.5 metres (67 feet). The minimum field of vision for safe driving is defined as 120 degrees wide and 20 degrees both above and below the horizontal. It is the driver’s responsibility to ensure that these requirements are met and to inform the DVLA if they are in doubt. Regular eye examinations are therefore recommended.
Which frames are best for driving?
You should choose a style that does not restrict your field of vision eg. Frames with thin rims or rimless, combined with sides fitted to the frame above eye level.
Which lenses are best for driving?
Plastic lenses are recommended, as they are lighter and safer should you be involved in an accident. Anti-reflection coated lenses reduce glare and reflections from oncoming lights, especially car headlights at night.
Are tinted lenses suitable for driving?
Tinted lenses are suitable for daytime driving under normal weather conditions. However, it is not recommended that they be used either at night, or in poor driving conditions.
VDU Operators
I work all day on a VDU, which lenses should I choose?
Choose lenses with an anti-reflection coating – they will help to reduce glare from your computer screen.
Should I wear my glasses when I use the VDU?
If you wear glasses generally, your eyes will feel more comfortable wearing your glasses on a VDU provided you have the recommended distance vision breaks away from your screen. Inform your Optometrist that you are a VDU operator and they will be able to offer you advice.
How will I know that I need an eye examination if I use a VDU?
You should visit the Optometrist if you suffer from persistent headaches, eyestrain, squinting, blurring of vision, double vision, dry eyes, watery eyes or excessive blinking. You should ensure that you have an eye examination every 2 years – this is particularly important if you are a regular VDU user.
Contact Lenses
Do I need spectacles if I wear contact lenses?
Absolutely YES!
The key to successful contact lens wear is to incorporate rest days without them. This is particularly important at the first signs of discomfort, blurring of vision or early signs of infection. Examples include: itchy eyes due to hay fever, if you have a head cold, sinus infection or flu, signs of conjunctivitis or if you are taking a course of medication not compatible with contact lens wear. It is recommended that contact lenses are not worn while flying, and definitely not when sleeping on a plane. This is why no contact lens wearer should be without a pair of spectacles. All too often contact lens wearers have omitted to update their spectacles to the current prescription or modern styling, resulting in a pair of spectacles that are not worn due to poor vision and cosmesis. Ensure that your spectacles are comfortable, provide equivalent vision to your contact lenses and are aesthetically pleasing.
Look good, feel good and see well!
Is it possible to get contact lenses for occasional use only?
Yes. Many spectacle wearers are happy using their glasses but want the option of contact lenses for certain occasions, eg. Playing sports and holiday breaks.
At HBD, your Optometrist will advise you of the best contact lens system to meet your requirements. Generally, daily disposable soft contact lenses are the most convenient when travelling.
How soon can I get contact lenses?
At HBD our extensive range of trial lenses allows us to fit and supply you with suitable lenses to commence wear on the same day. If you are new to contact lenses, a practical handling session will be provided to ensure that you are able to insert, remove and take care of your lenses before commencing wear. Our instructors are very patient and will spend several sessions with you if necessary, so you do not feel pressured and can take your time as you enter the new world of contact lenses.
Is it OK to sleep in my contact lenses?
Unless our Contact Lens fitter has specifically said that your contact lenses are suitable for regular overnight wear, the answer is NO. Several designs are suitable for occasional overnight wear, but check with your Optometrist first.
Can I wear contact lenses?
Yes – in most cases you will be able to use contact lenses. Certain individuals with unusual prescriptions or poor health may not be suitable.
Spectacles
How quickly can you make up my spectacles?
As we assemble our spectacles in our own workshop, they may take as little as 1 hour to make up. Certain specialised jobs require extra care and may take a little longer. Lenses and frames that need to be ordered from the manufacturers may delay the process, but our Dispenser will advise you of the likely timescale before we proceed.
How thick will my spectacle lenses be?
This depends on your prescription, the type of lenses you choose and the frame style. Generally, the higher the prescription the thicker the lens will be. Use of high index materials, reduction in lens diameter and choosing a frame with a full rim around the lens are all methods of keeping the lens thickness to a minimum. Ultra thin 1.74 index plastic lenses are now available to bring the thickness of plastic lenses more in line with the thinner glass lenses. Our HBD dispensers will be happy to advise you on the best frame and lens choices to suit your prescription.
What are the advantages of plastic over glass lenses?
Plastic lenses are lighter and have 3x the impact resistance of glass lenses. Glass lenses are generally thinner, are more durable to scratches and have slightly higher light transmission than standard plastic lenses.
What are photochromic lenses?
These are lenses, both in glass and plastic, which change from a relatively clear state to dark sunglass tint when exposed to sunlight and UV radiation. Typical brand types of these lenses are Reactolite and Transitions.
What are polarised lenses?
These are specialised tinted lenses that eliminate reflected light from surfaces in addition to direct glare from bright objects. This is very useful for fishermen who have to see through the surface of the water, while having to ignore annoying reflections. They are also of benefit to skiers and sailors.
These lenses can be made up with or without your prescription.
Glossary of Terms
The following explanations are intended as a general description of terms you may encounter from a visit to your Optometrist. If you are in any way concerned with the condition of your eyes, you should seek out medical assessment.
1. Anti-Reflection coatings
A coating on the lens surface to enhance the visual performance and cosmetic appearance of your spectacles.
2. Astigmatism
A refractive error in your prescription, caused by an ovalisation of the cornea or crystalline lens, that results in a ‘ghosting’ of your vision.
3. Bifocal Lenses
Provide clear vision at two ranges, generally far and near, with a visible dividing line between them.
4. Cataract
Opacity of the crystalline lens inside your eye.
5. Cornea
The clear front surface of the eye.
6. Conjunctiva
The tissue surrounding the cornea, extending over the ‘white’ of your eyes to line the inner surface of your eyelids.
7. Conjunctivitis
Inflammation of the above tissue.
8. Diplopia
A condition where objects are actually seen double – not to be confused with the ‘ghosting’ effects that can be seen with astigmatism.
9. Glaucoma
Damage to the optic nerve caused by multiple factors, including changes in intra-ocular pressure.
Increasingly common in the over 40 age group and often symptom free in the early stages.
Symptoms include peripheral field loss, tunnel vision and (if not treated early), blindness. Regular eye examinations are recommended when you exceed 40, as advancing age and family history increase the risk of developing this condition.
10. High Index Lenses
Spectacle lenses made from denser glass or plastic materials, resulting in thinner designs – generally used for high prescriptions only.
11. Interview Lenses
Specialised spectacle lenses for close work that have an extended design to incorporate reading and VDU distances.
12. Iris
The coloured part of your eye, which changes the size of your pupil to regulate the amount of light entering your eye.
13. Laser refractive surgery
The permanent re-shaping of the cornea to eliminate myopia (short sightedness), and to a lesser extent astigmatism and hyperopia (long sightedness), by the use of a laser.
14. Macular Degeneration
A common degenerative condition that affects the central, macular area of the retina in the over 60 age group. Divided into 2 common types: dry macular degeneration (slow to develop and not currently treatable) and wet macular degeneration (rapid onset and treatable if diagnosed early).
15. Myopia
Near-sightedness causing distant images to be out of focus.
16. Multi-focal lenses
Spectacle or contact lenses with more than one refractive correction allowing a clear focus at all distances.
17. Optic Nerve
Made up from the nerve fibres of the rods and cones of the retina, the Optic Nerve conveys visual information from the eye to the brain.
18. Orthokeratology
The process of re-moulding a cornea to eliminate myopia (short sightedness), by the wearing of a specially designed contact lens overnight. Completely reversible on cessation of lens wear – unlike laser surgery where the effects are permanent.
19. Polarised Lens
A spectacle lens designed to cut out annoying reflections from surfaces.
20. Polarised Light
Light that is reflected off a flat surface.
21. Presbyopia
A gradual loss of lens flexibility with age, making it increasingly difficult to focus on close-up tasks. Correctable by spectacle or contact lenses.
22. Pupil
The aperture in the centre of the iris that allows light through to the retina.
23. Retina
The layer of light receptors at the back of the eye.
24. Single Vision Lenses
Spectacle or contact lenses that allow viewing at only one distance eg. Distance glasses or reading glasses.
25. Sports Vision Eyewear
Corrective eyewear used for sports.
26. Trifocal Lenses
A multi-focal lens divided into distance and near sections, but also incorporating a mid distance section for viewing objects at arms length. A visible dividing line separates each section of the lens.
27. Varifocal Lenses
A specialised type of multi-focal lens that shows a smooth, invisible transition between the various sections allowing a clear focus at all distances.