People over 40 often begin to notice that it becomes difficult or impossible to focus on things up close and that their near vision has become blurry.
This condition is known as presbyopia, and it occurs gradually and naturally as a result of advancing age. Presbyopia is inevitable and is caused by the loss of elasticity of the lens in the eye, which makes the lens harden. As a result of this hardening, the eye is no longer able to focus on close objects because the light now focuses behind the retina instead of directly on it when reading.
Bifocal and multifocal contact lenses address presbyopia by offering both distance vision correction and near vision correction. These contact lenses can accommodate multiple different prescriptions in a single lens so that the wearer can focus clearly on objects at a wide range of distances, whether they are reading or driving.
Multifocal contact lenses have a range of powers similar to progressive eyeglass lenses in each lens. Different bifocal and multifocal contact lenses work in different ways, depending on the design of the lens. The designs fall into two basic groups:.
Simultaneous vision designs. These multifocal contact lenses have specific regions of the lens designated for far and near and sometimes intermediate viewing.
Depending on the object being viewed, the wearer's eye uses the region s of the lens that provide the sharpest vision. There are two types of simultaneous vision designs: concentric and aspheric see illustration.
Segmented designs. These rigid gas permeable multifocal lenses are designed much like bifocal and trifocal eyeglasses : the center and top portions of the lens contain the appropriate power for viewing distant objects, and the lower portion of the lens has added magnifying power for viewing near objects. Segmented designs sometimes are called alternating or translating designs. Concentric multifocal contact lenses typically contain the lens power for seeing distant objects in the center of the lens, which is surrounded by concentric rings of near and distance powers of your bifocal contact lens prescription.
Typically, at least two concentric power rings are within your pupil area in normal lighting, but this varies as your pupil dilates and constricts due to varying light conditions. Concentric bifocal lenses can be made of either soft or rigid gas permeable RGP or GP contact lens materials. Some concentric bifocal contacts have a center-distance design D for your dominant eye and a center-near design N for your non-dominant eye. The design of aspheric multifocal contact lenses is similar to that of progressive eyeglass lenses — there's a gradual change in power from far to near, with no visible lines in the lenses.
Your optometrist may determine that wearing reading glasses over distance contact lenses is the best option for you. This will help you see things up close when necessary. This is a great method in decreasing peripheral distortion which is generally caused by progressive eyeglasses.
If you prefer glasses over contacts, there are eyeglasses lens options that will help correct presbyopia as well. We offer both progressive and bifocal lenses , as well as a special office progressive lens called DualView. Clear vision is only one click away! Put your personality, style, and vibe front and centre. Glasses are one of the most expressive things you can wear, and if staying on….
When it comes to glasses, there are plenty of…. Do your glasses fog up every time you wear a face mask or other face coverings? Ever see the mist overtaking your lenses with every breath that you exhale? When you breathe out warm…. And, thanks to prescription sunglasses, you can now frolick fashionably while seeing…. Aspheric simultaneous vision lenses blend the different powers together across the lens, so there is a gradual change from near powers to far powers. Bifocal and multifocal lenses are available in a variety of materials.
Vision insurance can make getting the right lenses simple and affordable. Traditional soft contact lenses that are designed to be used part time. They are comfortable and the eyes adjust to them relatively easily. Silicone hydrogel soft lenses that let even more oxygen into your eyes than traditional soft lenses. Rigid gas permeable lenses that allow oxygen to reach your eyes. This can keep your eyes healthier, but it may take your eyes more time to adjust.
These lenses are designed to be worn every day. Disposable lenses that are thrown out at regular intervals. They are then replaced with fresh lenses. Hybrid lenses that have a rigid gas permeable section in the middle and softer material on the outside to increase comfort and make it easier for the eyes to adapt to the lenses.
Every situation is unique, and the lenses that work for your friend may not be comfortable for you. The type of lenses you need will depend on your vision, your health, your age, your personal preference, and more. Your eye doctor can help you weigh your options and choose the best solution.
In some cases you may need to try out a variety of lenses before determining the best fit for you. You may also need to make adjustments as your eyes continue to change. Not covered for vision? Get an individual plan, customized for you — including where you want to use it: at the doctor, in a retail location, or even online. In the s, Dutch ophthalmologist Herman Snellen had the vision pun intended to create an eye chart to help doctors quickly measure the visual a Understanding The Benefits of Eye Exams.
The Benefits Of Eye Exams You head to the doctor for a fever or a physical and to the dentist for a sore tooth or a cleaning, but what about your e Optical illusions play on the translation between what your eye sees and what your brain perceives. Click through this collection of optical ill VSP was founded in by a group of optometrists who wanted to provide access to affordable, high-quality eye care to the world.
VSP is the only national not-for-profit vision care company. We reinvest in our members and the community through the advancement of optometry, eyewear donations, and mobile clinics to help connect people in need with a local VSP network doctor.
Through this exam, doctors get a better view of your eyes and look for eye health problems such as glaucoma, and diabetic eye diseases while looking for signs of serious health conditions like high blood pressure. With VSP, you get choice. The name Vision Service Plan and the registered logo s , service mark s , and trademark s owned by Vision Service Plan or any of its subsidiaries or affiliates, and the contents of this site may not be used in any advertising or publicity, or other use without the prior explicit written permission of Vision Service Plan VSP.
Visionworks is an affiliate of Vision Service Plan. VSP makes no representations about the suitability of this information for any purpose. It is provided "AS IS" without express or implied warranty, including, but not limited to, the implied warranties of merchantability, or fitness for a particular purpose. In no event shall VSP be liable for any special, indirect or consequential damages or any damages whatsoever resulting from loss of use, data or profits, whether in action in contract, negligence or other tort action, arising out of or in connection with the use or performance of this information.
VSP has taken reasonable steps to ensure that the information on this site is accurate and timely. VSP, however, assumes no responsibility for any errors or omissions on this site or for the accuracy, truthfulness, or content of other documents that are referenced or linked to this site.
Nor does VSP make any commitment to update the information contained herein. This publication and other documents are subject to change without notice.
Health information content appearing is not intended as, and shall not be received or construed as patient-specific advice or a substitute for patient-specific advice. Links to documents outside of this publication are provided as a convenience and do not necessarily reflect the views or opinions of the staff or management of VSP. Links to such documents do not in any way suggest VSP's endorsement of any product or service specified therein. Links to documents outside of this publication may be found to contain offensive material or may further link to pages that may contain offensive material.
VSP's Eye Care Information provides basic eye care information to encourage overall eye health and wellness education.
Members are encouraged to review benefit information on vsp.
0コメント