vision lo: to know how lenses can be used to correct problems with vision can you come up with any...

9

Vision LO: To know how lenses can be used to correct problems with vision Can you come up with any conditions that can affect the eye or your vision?

Upload: gwendolyn-paul

Post on 17-Jan-2016

215 views

Category:

Documents

0 download

Report

Download

Tags:

Embed Size (px):

TRANSCRIPT

Page 1: Vision LO: To know how lenses can be used to correct problems with vision Can you come up with any conditions that can affect the eye or your vision?

Vision

LO: To know how lenses can be used to correct problems with vision

Can you come up with any conditions that can affect the eye or your vision?

Page 2: Vision LO: To know how lenses can be used to correct problems with vision Can you come up with any conditions that can affect the eye or your vision?

How the lens works:

Page 3: Vision LO: To know how lenses can be used to correct problems with vision Can you come up with any conditions that can affect the eye or your vision?

Short and long sightedness

Short sight occurs where the eye cannot focus on distant objects. The uncorrected image is formed in front of the retina. The muscles cannot make the lens thin enough to focus the image.

– What type of lens is used to correct short sight?

Long sight occurs when the eye cannot focus on nearby objects. The uncorrected image is formed behind the retina.

– What type of lens is used to correct long sight?

Page 4: Vision LO: To know how lenses can be used to correct problems with vision Can you come up with any conditions that can affect the eye or your vision?

21/04/2321/04/23

Using lenses to correct visionShort Long

Page 5: Vision LO: To know how lenses can be used to correct problems with vision Can you come up with any conditions that can affect the eye or your vision?

Comparing the eye to a camera

The Eye The Camera

Type of Lens Variable focus converging lens

Fixed focus converging lens

Focussing Adjustment Ciliary muscle alters the lens thickness

Adjustment of the lens position

Image Real, inverted, magnification less than 1

Real, inverted, magnification less than 1

Image Detection Light sensitive cells on the retina

Photographic film or CCD sensors (digital)

Brightness Control Iris controls width of pupil Adjustment of aperture ‘stop’

Page 6: Vision LO: To know how lenses can be used to correct problems with vision Can you come up with any conditions that can affect the eye or your vision?

Lens power The power of a lens is defined as:

1 focal length in meters

The unit of power is the dioptre (D)The type of lens is indicated by:

-a positive value for a converging lens-a negative value for a diverging lens

What is the power of a converging lens of focal length 0.05m?

Page 7: Vision LO: To know how lenses can be used to correct problems with vision Can you come up with any conditions that can affect the eye or your vision?

Spec Savers

Opticians are continually trying to design glasses and contacts to be as thin as possible. What factors do you think will affect the thickness of glasses lenses?

– The refractive index and the curvature of the lens

The greater the refractive index or the greater the curvature of the lens surface the greater the power of the lens.

For a lens of a given focal length, the greater the refractive index of the lens material, the flatter and thinner the lens can be manufactured. This is because the lens surface would be less curved.

Page 8: Vision LO: To know how lenses can be used to correct problems with vision Can you come up with any conditions that can affect the eye or your vision?

Photographic evidence The camera never lies… Is this statement true? Can you identify whether

these images are real or fake:

Real Fake

Fake

FakeReal

Page 9: Vision LO: To know how lenses can be used to correct problems with vision Can you come up with any conditions that can affect the eye or your vision?

Task and Extension

How can lenses be used to correct long and short sightedness?

Use diagrams and your knowledge of lenses to explain how laser eye surgery works to correct vision defects?

Trial Lenses in Vision Correction Douglas A. Kerr Issue 2 December

FEP Vision · 2021. 1. 11. · Trifocal Lenses Up to $136 Up to $136 Lenticular Lenses Up to $136 Up to $136 Contact Lenses Up to $150 Up to $130 Medically Necessary Contact Lenses

NEW PROGRESSIVE LENSES FOR ALL-DAY-LONG VISION …

T6 W3 Science Jelly Vision - seamillsprimary.org.uk€¦ · T6 W3 Science Jelly Vision . Jelly vision Can jelly play TRICKS with your EYES? Find out yourself with these jelly lenses

Computer Vision Cameras, lenses and sensors Marc Pollefeys COMP 256

Cathy Cataracts - Miller Eye Center · 2018. 11. 5. · of clear, sharp vision. These lenses restore cataract-impaired vision and can correct for nearsightedness, farsightedness and

of Catholic ParishesDr.Lynn Carli and Dr.John Knuth 535 South Monroe Ave. 435-9511 Complete Family Vision Care Contact Lenses, Frames and Lenses Repairs and Adjustments Contact Lenses

Vision Certificate of Coveragedoas.ga.gov/assets/Human Resources Administration... · Prescription Lenses (including factory scratch coating, polycarbonate lenses for children under

Eye screening and care - Outback Vision · 2019. 9. 4. · Optometrists: can screen for eye disease and vision disorders, prescribe glasses or contact lenses to correct vision and

Line Scan Camera | Machine Vision Lenses | Machine Vision

Advanced Computer Vision Cameras, Lenses and Sensors

FA & Machine Vision Lenses

Specialty Intraocular Lenses Can Reduce Your Dependence …...Specialty Intraocular Lenses Can Reduce Your Dependence on Glasses —Continued on page 2. See “Intraocular Lenses.”

WHY EDOF INTRAOCULAR LENSES? FOR EXCELLENT VISION QUALITY

A LOOK AT YOUR VSP VISION COVERAGE6938719e...Standard progressive lenses Premium progressive lenses Custom progressive lenses Average savings of 20-25% on other lens enhancements $0

SINgle VISIoN leNSeS - VSP Optics · PDF fileUNITY Single Vision lenses offer the latest technology in precision freeform single vision lens processing in a wide range of materials

496-7457 · teens or early adulthood. Nearsightedness can be corrected by glasses, contact lenses or refractive surgery. Glasses and contact lenses can be adjusted if vision changes

Sagicor Online Provider Claims Listing - RHAND …...Forsight Vision Eye Exam, Frames, Lenses Frederick Street, POS 623-1874 JC Vision Eye Exam, Frames, Lenses Carlton Ave & Luckput

Global Computer Vision 1. Capturing the field’s image 1.1 ... · Global Computer Vision 1. Capturing the field ... the field using a system of lenses that can keep the field distortion

NO TELESCOPIC LENSES PERMITTED SEE REVERSE SIDE FOR VISION

SINGLE VISION LENSES...That’s why HOYA’s iD Single Vision is the first aspheric lens design based entirely on how your eyes view your surroundings. SINGLE VISION iQ LENSES LET

Contact Lenses for Better Vision and Comfort

Computer Vision - University of California, Berkeleyee290t/fa09/lectures/cameras_polleyfes.pdfComputer Vision Cameras, lenses and sensors Marc Pollefeys COMP 256. Computer Vision

LED Pattern Projector - Smart Vision Lights integrate standard C-mount 2/3” lenses. Telecentric lenses can also be used for telecentric pattern projection. Projector lenses and pattern

CAN I HAVE CONTACT LENSES ?

Topic 4: Lenses and Vision. Essential Learning Outcome I can explain the use of concave and convex lenses in objects such as microscopes, eye glasses,

PROGRESSIVE LENSES SINGLE VISION LENSES · i.Scription® by ZEISS The new prescription for better vision ™ The 100% Solution ZEISS customized lenses reach new heights with i.Scription

2d barcode standard for lenses - The Vision Council

HERITAGE INFORMATION SERIES...heritage photography. Either fixed focal length lenses or zoom lenses can be Either fixed focal length lenses or zoom lenses can be used and should cover

Cheyenne Vision Clinic Newsletter · to order contact lenses and have them shipped free directly to you. Lost or torn contact lenses and solution can also be shipped free to you

UNITY CVxpression COMPUTER VISION LENSES - VSPvspopticsgroup.com/pdf/CVxpression-sell-sheet.pdf · UNITY CVxpression Computer Vision Lenses Unlike traditional computer vision lenses,

Vision Hardware Program Billing Guide · 7/1/2020 · - Contact lenses that are designed to be worn for longer periods than daily wear (remove at night) lenses. These can be conventional

ZEISS SmartLife Lenses · products, including single vision, digital and progressive addition lenses. These types of lenses and their uses are well known to eyecare professionals

Transformations to a Standards Aligned System Many Lenses, One Vision

Photochromic Lenses - VisionEase · the photochromic lens they always wanted VISION EASE Photochromic Lenses With VISION EASE Photochromic Lenses, they’ll get the performance they