Spectacles consist of lenses held in a frame that extends towards the ears. The frame holds the lenses and comes in various materials like plastic, metal, and nylon. Lenses can be made of glass or plastics like CR-39, polycarbonate and Trivex. Lens forms include flat lenses, curved lenses like meniscus and toric lenses. Spectacles can be single vision, bifocal, trifocal or progressive. Additional lens features include coatings like anti-reflective, scratch-resistant, UV and photochromic coatings.
This presentation is mainly focused on progressive addition lenses along with the brief description of single vision reading lenses ,bifocal and trifocals which are the other options available for the management of presbyopia. It also include a short description on the fitting of the PAL. PAL is the most used option worldwide for the management of presbyopia .PAL is also used in the management of progressive myopia and the studies shows it is more effective than the bifocal lenses. PAL are more effective in myopia management when the myopia comes along with the near esophoria and accommodation lag. In this modern century personalised progressive lenses are the most effective in matching the need of the patients.
progressive lenses, multifocal lenses, polyfocal lenses, lenses for presbyopia, bifocal lenses, lenses for near reading, lenses for the elderly, above age 40
progressive addition lenses , needs of PAL, permanent and temporary marking of PAL, parts of PAL, design of PAL, Progressive corridor and their importance ,theory behind the PAL,Sand box analogy,OPTICAL DESCRIPTION OF PROGRESSIVELENSES,patterns of PAL,Advantage and Limitation of PAL,fitting of PAL and Frame selection for PAL,measurements for fitting,verification of PALs,
traubleshooting in PALs,Brands and special design of PALs
This presentation is mainly focused on progressive addition lenses along with the brief description of single vision reading lenses ,bifocal and trifocals which are the other options available for the management of presbyopia. It also include a short description on the fitting of the PAL. PAL is the most used option worldwide for the management of presbyopia .PAL is also used in the management of progressive myopia and the studies shows it is more effective than the bifocal lenses. PAL are more effective in myopia management when the myopia comes along with the near esophoria and accommodation lag. In this modern century personalised progressive lenses are the most effective in matching the need of the patients.
progressive lenses, multifocal lenses, polyfocal lenses, lenses for presbyopia, bifocal lenses, lenses for near reading, lenses for the elderly, above age 40
progressive addition lenses , needs of PAL, permanent and temporary marking of PAL, parts of PAL, design of PAL, Progressive corridor and their importance ,theory behind the PAL,Sand box analogy,OPTICAL DESCRIPTION OF PROGRESSIVELENSES,patterns of PAL,Advantage and Limitation of PAL,fitting of PAL and Frame selection for PAL,measurements for fitting,verification of PALs,
traubleshooting in PALs,Brands and special design of PALs
This slide gives you the basic information about the types of photography lenses used worldwide.
Image source: Google Images
*the content provided here has been copied from various sources. no authentication proof is available.
The lenses used for photography worldwideAmit Dash
This slide gives you the basic information about the types of photography lenses used worldwide.
Image source: Google Images
*the content provided here has been copied from various sources. no authentication proof is available.
How to protect your eye?
With sunglasses? Mirror glasses? Tinted or polarized glasses?
What is right tint colour for you?
What are antireflection coat glasses?
Anti ulcer drugs and their Advance pharmacology ||
Anti-ulcer drugs are medications used to prevent and treat ulcers in the stomach and upper part of the small intestine (duodenal ulcers). These ulcers are often caused by an imbalance between stomach acid and the mucosal lining, which protects the stomach lining.
||Scope: Overview of various classes of anti-ulcer drugs, their mechanisms of action, indications, side effects, and clinical considerations.
MANAGEMENT OF ATRIOVENTRICULAR CONDUCTION BLOCK.pdfJim Jacob Roy
Cardiac conduction defects can occur due to various causes.
Atrioventricular conduction blocks ( AV blocks ) are classified into 3 types.
This document describes the acute management of AV block.
Flu Vaccine Alert in Bangalore Karnatakaaddon Scans
As flu season approaches, health officials in Bangalore, Karnataka, are urging residents to get their flu vaccinations. The seasonal flu, while common, can lead to severe health complications, particularly for vulnerable populations such as young children, the elderly, and those with underlying health conditions.
Dr. Vidisha Kumari, a leading epidemiologist in Bangalore, emphasizes the importance of getting vaccinated. "The flu vaccine is our best defense against the influenza virus. It not only protects individuals but also helps prevent the spread of the virus in our communities," he says.
This year, the flu season is expected to coincide with a potential increase in other respiratory illnesses. The Karnataka Health Department has launched an awareness campaign highlighting the significance of flu vaccinations. They have set up multiple vaccination centers across Bangalore, making it convenient for residents to receive their shots.
To encourage widespread vaccination, the government is also collaborating with local schools, workplaces, and community centers to facilitate vaccination drives. Special attention is being given to ensuring that the vaccine is accessible to all, including marginalized communities who may have limited access to healthcare.
Residents are reminded that the flu vaccine is safe and effective. Common side effects are mild and may include soreness at the injection site, mild fever, or muscle aches. These side effects are generally short-lived and far less severe than the flu itself.
Healthcare providers are also stressing the importance of continuing COVID-19 precautions. Wearing masks, practicing good hand hygiene, and maintaining social distancing are still crucial, especially in crowded places.
Protect yourself and your loved ones by getting vaccinated. Together, we can help keep Bangalore healthy and safe this flu season. For more information on vaccination centers and schedules, residents can visit the Karnataka Health Department’s official website or follow their social media pages.
Stay informed, stay safe, and get your flu shot today!
Couples presenting to the infertility clinic- Do they really have infertility...Sujoy Dasgupta
Dr Sujoy Dasgupta presented the study on "Couples presenting to the infertility clinic- Do they really have infertility? – The unexplored stories of non-consummation" in the 13th Congress of the Asia Pacific Initiative on Reproduction (ASPIRE 2024) at Manila on 24 May, 2024.
micro teaching on communication m.sc nursing.pdfAnurag Sharma
Microteaching is a unique model of practice teaching. It is a viable instrument for the. desired change in the teaching behavior or the behavior potential which, in specified types of real. classroom situations, tends to facilitate the achievement of specified types of objectives.
The prostate is an exocrine gland of the male mammalian reproductive system
It is a walnut-sized gland that forms part of the male reproductive system and is located in front of the rectum and just below the urinary bladder
Function is to store and secrete a clear, slightly alkaline fluid that constitutes 10-30% of the volume of the seminal fluid that along with the spermatozoa, constitutes semen
A healthy human prostate measures (4cm-vertical, by 3cm-horizontal, 2cm ant-post ).
It surrounds the urethra just below the urinary bladder. It has anterior, median, posterior and two lateral lobes
It’s work is regulated by androgens which are responsible for male sex characteristics
Generalised disease of the prostate due to hormonal derangement which leads to non malignant enlargement of the gland (increase in the number of epithelial cells and stromal tissue)to cause compression of the urethra leading to symptoms (LUTS
Factory Supply Best Quality Pmk Oil CAS 28578–16–7 PMK Powder in Stockrebeccabio
Factory Supply Best Quality Pmk Oil CAS 28578–16–7 PMK Powder in Stock
Telegram: bmksupplier
signal: +85264872720
threema: TUD4A6YC
You can contact me on Telegram or Threema
Communicate promptly and reply
Free of customs clearance, Double Clearance 100% pass delivery to USA, Canada, Spain, Germany, Netherland, Poland, Italy, Sweden, UK, Czech Republic, Australia, Mexico, Russia, Ukraine, Kazakhstan.Door to door service
Hot Selling Organic intermediates
Report Back from SGO 2024: What’s the Latest in Cervical Cancer?bkling
Are you curious about what’s new in cervical cancer research or unsure what the findings mean? Join Dr. Emily Ko, a gynecologic oncologist at Penn Medicine, to learn about the latest updates from the Society of Gynecologic Oncology (SGO) 2024 Annual Meeting on Women’s Cancer. Dr. Ko will discuss what the research presented at the conference means for you and answer your questions about the new developments.
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Ve...kevinkariuki227
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
ARTIFICIAL INTELLIGENCE IN HEALTHCARE.pdfAnujkumaranit
Artificial intelligence (AI) refers to the simulation of human intelligence processes by machines, especially computer systems. It encompasses tasks such as learning, reasoning, problem-solving, perception, and language understanding. AI technologies are revolutionizing various fields, from healthcare to finance, by enabling machines to perform tasks that typically require human intelligence.
These simplified slides by Dr. Sidra Arshad present an overview of the non-respiratory functions of the respiratory tract.
Learning objectives:
1. Enlist the non-respiratory functions of the respiratory tract
2. Briefly explain how these functions are carried out
3. Discuss the significance of dead space
4. Differentiate between minute ventilation and alveolar ventilation
5. Describe the cough and sneeze reflexes
Study Resources:
1. Chapter 39, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 34, Ganong’s Review of Medical Physiology, 26th edition
3. Chapter 17, Human Physiology by Lauralee Sherwood, 9th edition
4. Non-respiratory functions of the lungs https://academic.oup.com/bjaed/article/13/3/98/278874
3. SPECTACLE FRAME
The portion of spectacle which holds the
lenses containing the ophthalmic prescription
in their proper position in front of the eyes.
There are two part in a frame:
• Frame front
• Temples
10. Bridge
1. Regular bridge-rests on nose with full support.
2. Inset Bridge-it protects behind the frame plane
,so that the area of contact lies behind the lens
space
3. Saddle Bridge-combination of regular and insert
bridge
21. 1. GLASS LENSES
2. NORMAL INDEX LENSES :1.48-1.54
->Standard plastic CR-39
lenses
3. MEDIUM INDEX LENSES:1.54-1.64
->Polycarbonate lenses
->Trivex lenses
4. HIGH INDEX LENSES :1.64-1.74
5. ULTRA-HIGH INDEX LENSES :>1.74
->Plastic lenses
COMMON EYEGLASS LENS
MATERIALS
29. LENS FORMS
● FLAT LENSES
1. Biconcave or biconvex
2.Plano-concave or plano-
convex
● CURVED LENSES
1. Meniscus lens
2.Toric lens
3. Lenticular lens
4.Apheric lens
30. MENISCUS LENS
● Base curve
-SEMIFINISHED LENS
Base curve is added to
anterior surface and
optician grinds its
other surface to get
required power
● DEEP MENISCUS
LENS
● PERISCOPIC LENS
31. TORIC LENS
• Where one surface is spherical and other
surface is toroidal.
• What is toroidal surface?
if we visualise a cylinder its one axis is curved while
other is straight which is the axis of cylinder-> now
straight axis is also curved then surface will become
toroidal.
• Spherical lens is ground on anterior surface
and posterior surface is made toroidal
• Base curve used 6D
• Difference between base curve and curvature of
toric surface equals the cylindrical power
32. LENTICULAR LENSES
● Used for high power
● Central portion –
power
– aperture – 30mm
● Peripheral portion –
carrier – 1.2-2 mm
thinner than central
part
● Reduce the
weight of
spectacle and
aberrations
33. ASPHERIC LENSES
● used to make high plus
aphakic lenses by
modifying the lens
curvature peripherally to
reduce aberration and
provide better
peripheral vision
● Base curve for aphakic
lens is relatively flat.
35. SINGLE VISION OR UNIFOCAL
This lens provides correction only for a given
distance. This means that the optical power is
the same at every point on the lens’s surface.
Prescribed only for single vision:
• Myopia
• Hypermetropia
• Astigmatism
• Presbyopia
36.
37.
38.
39.
40. TRIFOCAL LENSES
Trifocals are eyeglasses with lenses that have
three regions which correct for distance,
intermediate (arm's length) and near vision
John Isaac Hawkins developed the trifocal lens
in 1827
Trifocals are mostly used by people with
advanced presbyopia who have been prescribed
2 diopters or more of reading addition
41. PROGRESSIVE LENSES
Progressive lenses are line-free multifocals
that have a seamless progression of added
magnifying power for intermediate and near
vision.
The junction between these distinctly different
power zones is defined by a visible "bifocal line"
that cuts across the center of the lens.
45. ANTI-REFLECTIVE COATING
Anti-reflective coating can reduce eyestrain caused from
glare, reflections, and the "halos" you see around lights at
night. It helps protect your lenses from scratches and
smudges, and can repel dust and water. This coating makes
your vision sharper and your eyes appear clearer behind
your lenses.
Some anti-reflective coatings reduce the amount of
reflected UV from the back of your lenses, providing the
best overall UV protection possible.
46. • Copper and gold coating reflect approximately 98%
of IR above 750 nm
Anti reflective coating glasses for IR
47. SCRATCH- RESISTANT COATING
• They are distracting and
can affect thr ability to see
clearly.
• Many have built in scratch
resistant coating nowadays
including high-index lense,
polycarbonate and trivex
lenses.
• These type of lenses are
treated front and back with
a clear, scratch-resistant
coating and have harder
surface wchich benfit
kidsfor greater durability.
48. UV COATING
• The cumulative exposure to UV radiation is harmful and
associated with age related eye problems->Cataract
and macular degeneration.
• Lenses that block 100% of both UV-A and UV-B help to
ward off Uv damaging effect.
• Nearly all high index plastic lenses and basic CR-39
plastic lenses require an added coating to provide
equal UV protection.
49. PHOTOCHROMIC LENSES
Photochromic lenses are optical lenses that darken on
exposure to specific types of light of sufficient intensity,
most commonly ultraviolet (UV) radiation. In the
absence of activating light the lenses return to their
clear state. Photochromic lenses may be made of
glass, polycarbonate, or another plastic. They are
principally used in eyeglasses that are dark in bright
sunlight, but clear in low ambient light conditions. They
darken significantly within about a minute of exposure
to bright light, and take somewhat longer to clear. A
range of clear and dark transmittances are available.
50. In one sort of technology, molecules of silver
chloride or another silver halide are embedded in
photochromatic lenses. They are transparent to
visible light without significant ultraviolet component,
which is normal for artificial lighting. In another sort of
technology, organic photochromic molecules, when
exposed to ultraviolet (UV) rays as in direct sunlight,
undergo a chemical process that causes them to
change shape and absorb a significant percentage of
the visible light, i.e., they darken. These processes
are reversible; once the lens is removed from strong
sources of UV rays the photochromic compounds
return to their transparent state.
51. PHOTOCHROMIC LENSES
A photochromic eyeglass lens (polymer film),
after exposure to sunlight with part of the lens
covered by paper.
Note the two levels of coloration around the
dark-light interface, arising from the fact that the
photochromic molecules are located in two thin
films (on the front and back surfaces of the lens).
53. ANTI- FOG COATING
• During cold climatic
conditions or during sports
activities or while wearing
masks, the spectacle
lenses may fog up.
• The anti-fog coatings
negates this problems by
eliminating the
condensation of moisture
on lenses that causes
fogging
54. TINTED LENSES
or tinted lens protects against UV
Colored
radiation.
They can also give you a high-contrast vision
experience even in glaring or diffuse light.
55. MIRROR COATING
• It is designed for a
purely cosmetic
purpose that allows
the eyes to remain
hidden from view
and adds glamour to
the glass.
• it comes in a variety
of colours such as
silver, gold and blue.
56. POLARIZED LENSES
Polarized lenses reduce glare reflected off surfaces,
making images appear sharper and clearer. They are
available for non-prescription and prescription
sunglasses, and can be worn indoors by light-sensitive
people, including post-cataract surgery patients and those
continually exposed to bright sunlight through windows.
Most polarized lenses provide UV protection, which is
important to maintaining healthy eye sight.