LENSES
By: Carmen Willings
teachingvisuallyimpaired.com Reports should indicate what a student's uncorrected and corrected visual acuities are. If a student's vision can be corrected, even mildly, they will typically be prescribed glasses or contacts. Why were the glasses prescribed?It is important to know why the glasses have been prescribed. Correcting a refractive error (such as myopia or hyperopia) is only one of the reasons that these may be prescribed. Glasses may be prescribed with a prism for a muscle imbalance or they may be recommended to protect the eyes. If the glasses are prescribed for near, they should be removed for distance viewing and vice versa if recommended by the doctor (some students will be able to leave them on as it will not have a significant impact). Glasses that are prescribed for myopia, or nearsightedness, will have a minus lens. Glasses prescribed for hyperopia will have a plus lens.
Types of LensesThe type of lenses that are prescribed can tell you a lot about the student's eye condition. The stronger the lens, the more significant the uncorrected vision. Keep in mind that even if a student is prescribed glasses, it doesn't necessarily mean that the student's vision can be fully corrected. This is because glasses cannot correct all types of visual impairments.
A convex, or plus lensA convex lens bulges outward, converges light rays and increases the size of an image being viewed. A plus lens directs light rays entering the eye so they focus on the retina instead of behind the retina as convex lenses correct hyperopia, a condition in which the eye is underpowered. Lens power that is greater than +12D could mean that the student has no crystalline lens (due to cataract surgery or aphakia) or the student has extreme farsightedness.
A concave, or minus lensA concave lens bulges inward, diverges light rays and decreases the size of the image received or can be used to converge light rays so that they focus on the retina, rather than in front of it. A very strong minus lens indicates extreme nearsightedness, also referred to as high myopia.
Plano lensesA plano lens does not bulge inward or outward and is not for correction in eyeglasses. A student may be prescribed plano lenses if they have no vision in one eye and the lens is used to "balance" the prescription for the other eye. It may also be used for cosmetic reasons or for safety reasons.
Prism LensesPrism lenses are often prescribed for persons who have strabismus for the purpose of redirecting the rays of light entering the eye. Prisms may also be used for persons with visual field neglect to cue the person that additional information exists in the neglected field.
Other Terms...
Sample Eyeglasses Prescription
Learn More...All About VisionGary Heiting, OD has written a great article for All About Vision entitled "How to Read Your Eyeglass Prescription." This information can be very helpful when interpreting the eye report!
|
Free MembershipSign up for free membership to access the FREE downloadable templates, handbooks and handouts on the Printables page. Simply click on the Log In | Register link in the navigation bar. If you haven't joined yet, you will be prompted to create a password.
TVI's Guide Complete Set Bundle + BONUS Resources
$100.00
Buy together at a reduced price and get BONUS resources!
TVI’s Guide to Teaching the ECC: An Activities Based Curriculum for Teaching Students who are Blind or Visually Impaired The TVI’s Guide to Teaching the ECC is a digital pdf available for download. It is designed specifically for fellow itinerant Teachers of Students with Visual Impairments (TVI’s), and consists of over 400 activities and topic areas of discussion for instructing students in the Expanded Core Curriculum. The activities are age-neutral and multi-sensory and therefore can meet the needs of the broad range of students served on an itinerant caseload serving. The activities can be individualized to the students various learning modalities and scaffold in order to challenge students but ensure success. Select those activities that align with the student’s learning objects based on the student’s unique visual needs and academic and developmental level. In addition to the core activity areas, each of the 32 Thematic Units incorporates additional unique ECC concepts and skills providing you with a years’ worth of activities. These units are cyclical and can be used repeatedly to help students build on prior knowledge and develop a deeper understanding of concepts. Each unit includes suggestions for activity adaptation associated with the unit. These include lists of objects, possible community-based experiences, environmental print, poems, children & young reader books, children's songs, pop culture songs, movies, and websites. In addition to the book, the following two supplements are included: ·      TVI’s Guide to the ECC Concept Checklist ·      TVI’s Guide to the ECC Activities Checklist For complete product details and additional images, visit the TVI's Guide product page. TVI's Guide to the ECC Product details ·      Digital pdf download: 346 pages (11 pt font) ·      Publisher: Teaching Students with Visual Impairments ·      Author: Carmen Willings ·      Language: English Visual Efficiency & Near Magnifier Fluency Worksheets: TVI's Guide to the ECC Grab and Go Supplements The Near Magnifier Fluency Worksheets is a Grab and Go supplement to the TVI's Guide to Teaching the ECC. This workbook is a pdf download that can be printed on demand for use with students. It contains five different types of worksheets for developing visual motor skills and near magnifier fluency skills particularly with the use of a video magnifier. As a companion to the TVI’s Guide to the ECC, the worksheets correspond to each of the 32 ECC Thematic units. The worksheets, along with a list of environmental print for each thematic unit, are designed to help students refine their visual motor skills while reinforcing ECC concepts presented in the thematic units.  For complete product details and additional images, visit the Visual Efficiency & Near Magnifier Product Page. Visual Efficiency & Near Magnifier Fluency Worksheet Details: ·      Digital pdf download: 210 pages ·      Publisher: Teaching Students with Visual Impairments ·      Author: Carmen Willings ·      Language: English Thematic Keyboarding & Braille Fluency and Maintenance Worksheets: A TVI’s Guide to Teaching the ECC Grab & go Supplement The Thematic Keyboarding & Braille Fluency and Maintenance Grab and Go ECC worksheet packet is a print on demand workbook that contains worksheets in print and simulated braille to use for data collection. Present the student with a hard braille copy and use the worksheets to document accuracy and fluency in reading braille. As a companion to the TVI’s Guide to the ECC, the worksheets correspond to the ECC Thematic activities presented in the curriculum guide. These word lists and sentences will help the student refine their keyboarding or braille reading skills while bridging ECC concepts presented in the thematic units. Although the lists and passages can be produced using a manual braillewriter, you may also copy and paste the passages into any braille translation software for quick production on an embosser. They may also be entered into a typing program such as APH’s Talking Typer to build keyboarding fluency. For complete product details and additional images, visit the Thematic Keyboarding & Braille Fluency & Maintenance Product Page Thematic Keyboarding & Braille Fluency Worksheet Details: ·      Digital pdf download: 338-page print and simulated braille worksheets ·      Publisher: Teaching Students with Visual Impairments ·      Author: Carmen Willings ·      Language: English Thematic Vocabulary Cards and Checklists: Grab & Go ECC Supplement The Thematic Vocabulary Cards and Checklists Grab and Go ECC supplement is a 446 page pdf downloadable print on demand workbook that includes 2940 vocabulary card on 3 1/2" x 2" templates divided by each of the 32 Thematic Units along with a checklist of each unit words in print and simulated braille. As a companion to the TVI's Guide to the ECC, the vocabulary cards correspond to the ECC Thematic activities presented in the curriculum guide. Additional Use: Teachers of Students with Visual Impairments can have a extremely varied caseloads. It is possible to go several years without having a student on your caseload who requires braille instruction. Like other skills, if you do not practice your braille regularly, it is easy to lose those skills. Use these checklists and cards to maintain your braille skills. Fold the checklist along the line dividing the print from the braille. Choose to either read the print and produce the word in braille using a braillewriter or read the simulated braille and decode it. Finally, these vocabulary cards and checklists may be used with family members or peers who are interested in learning and practicing the braille code. For complete product details and additional images, visit the Thematic Vocabulary Cards & Checklists Product Page Thematic Vocabulary Cards and Checklists Details: ·      Digital pdf download: 446-page print on demand resource ·      Publisher: Teaching Students with Visual Impairments ·      Author: Carmen Willings ·      Language: English BONUS! Lotto Cards The LOTTO Cards Grab and Go Supplement includes 37 theme related unit cards along with activity suggestions that support activities within the TVI's Guide to Teaching the ECC. On My Way File Folder Cards Print and use these cards to represent locations the student may visit that are related to the current thematic unit. Use these with the On My Way File Folder Game outlined in the TVI's Guide to Teaching the ECC p. 27. NEW! Access to TVI's Guide Bonus Membership Pages Note: All products are digital pdf downloads. Once you make your purchase you will be directed to an order confirmation page where you will find the download link. This download will also be included on the receipt sent to the email address you provide. The pdf download can be found directly under the order number. If you encounter any difficulty, please let me know and I can assist you. |
