An optician is an individual who fits eyeglasses or contact lenses by filling a refractive prescription from an optometrist or ophthalmologist.[1] They are able to translate and adapt ophthalmic prescriptions, dispense products, and work with accessories.[2] There are several specialties within the field.
A dispensing optician is anyone who prepares, fits, and dispenses prescription lenses, spectacles, eyeglasses, contact lenses, or any other type of vision-correcting optical device to the intended user. They may interpret optical prescriptions issued by an ophthalmologist, optometrist, or physician for the lab optician who fabricates vision-correcting optical lenses. They also measure inter-ocular or pupillary distances, vertex distances, pupil fitting heights, and frame angles to determine the proper position of vision-correcting lenses. In addition, they adapt, modify, or align frames with vision-correcting lenses to the face of the intended wearer, Dispensing opticians must have a basic knowledge of laboratory techniques such as lens surfacing and lens preparation.[3]
Mechanical optician, lab optician, or ophthalmic lab technician
Ophthalmic laboratory technicians must understand optics and how to use machinery in order to surface, coat, edge, or finish lenses according to specifications provided by dispensing opticians. They typically insert lenses into frames, also called glazing, to produce finished glasses and conduct all quality and safety testing required by the respective local and country regulations. Although most lenses are designed with fully automated equipment, such as computer-based generators, automatic edgers, and lens measurement instruments, a highly-skilled lab optician will often finish lenses by hand for more difficult prescriptions and lens designs in order to have the best-finished outcome.[4][5]
Contact lens fitter or contact lens technician
Contact lens fitters may work independently or under the direction of an ophthalmologist or optometrist to fill a doctor's prescription for contact lenses. A patient must obtain a prescription for contact lenses from a physician and then the fitter will review contact lens handling, fitting, and follow-up care. Contact lens fitters must have computer skills, communication skills, and an understanding of medical-legal implications.[6]
Ocularist
An ocularist is a trained technician who specializes in fitting a patient with a prosthetic eye after management by an ophthalmologist. Ocularists are trained in assessing the status of the orbit, fabricating and fitting a cosmetic ocular prosthesis, and periodically monitoring the prosthesis and related tissues. They ensure the correct fitting, shaping, and painting of ocular prostheses. The ocularist also educates the patient on handling and care of the prosthesis. Ocularists provide long-term care through follow-up examinations for evaluation and polishing of prostheses.[7]
Work environment
Corporate practice
Corporate practices may require more night and weekend work hours than other work environments due to the longer hours of the corporate chains. Many who work for them report the trade-off is greater room for growth, higher pay, and better benefits due to the larger scale of the employer. Purchasing of goods is conducted by the corporate headquarters and not by individuals at the locations.
Independent practice
Owned by the optician themselves, opticians who operate independent practices have all of the responsibilities of an entrepreneur/business owner as well as an optician. In the United States, due to certain local and state regulations, opticians cannot employ optometrists in various areas and are limited in some vision discount plans they can accept. This means they must rely more heavily on walk-in consumers than those who are owned by a doctor.[8]
Optometrist or ophthalmologist office
A smaller, more intimate environment than corporate or clinical, doctor-owned practices usually do not require as many evening or weekend hours as corporate locations; however, every medical office is different and will have a unique set of features and characteristics.
Hospitals and clinics
Opticians working in a hospital or clinic typically oversee patient care, administer treatment and operate medical equipment under the supervision of an ophthalmologist or optometrist.
Lab manufacturing
This role typically does not work directly with patients and it is centered around the use of high-tech equipment and hand-held tools.
"He Nose The Eyes". 1910 advertisement for Dr. Felix Gaudin, "Graduate Optician", New Orleans
The first known artistic representation of eyeglasses was painted by Tommaso da Modena in 1352. He did a sequence of frescoes of brothers efficiently reading or replicating manuscripts; one holds a magnifying glass while the other has glasses suspended on his nose. Once Tommaso had established the example, other painters positioned spectacles on the noses of many of subjects, almost certainly as a representation of wisdom and respect.
One of the most noteworthy developments in spectacle production in the 15th century was the introduction of concave lenses for the myopic or nearsighted. Pope Leo X, who was very myopic, wore concave spectacles when hunting and professed they enabled him to see clearer than his cohorts.
The first spectacles utilized quartz lenses since optical glass had not been developed. The lenses were set into bone, metal and leather mountings, frequently fashioned like two small magnifying glasses with handles riveted together and set in an inverted V shape that could be balanced on the bridge of the nose. The use of spectacles extended from Italy to Germany, Spain, France and Portugal.
From their inception, eyeglasses posed a dilemma that wasn't solved for almost 350 years: how to keep them on the bridge of the nose without falling. Spanish spectacle makers of the 17th century experimented with ribbons of silk that could be attached to the frames and then looped over the ears. Spanish and Italian missionaries carried the new models to spectacle wearers in China. The Chinese attached little ceramic or metal weights to the strings instead of making loops. In 1730 a London optician named Edward Scarlett perfected the use of rigid sidepieces that rested atop the ears. This perfection rapidly spread across the continent. In 1752 James Ayscough publicized his latest invention, spectacles with double hinged side pieces. These became very popular and appear more often than any other kind in paintings and prints of the period. Lenses were fabricated of tinted glass as well as clear. Ayscough felt that the clear glass lenses gave an unpleasant glare. In Spain in 1763 Pablo Minguet recommended turquoise, green, or yellow lenses but not amber or red.
Europeans, in particular the French, were self-conscious about the use of eyeglasses. Parisian aristocrats used reading aids only in private. The gentry of England and France used a "perspective glass” or monocular which could be concealed from view easily. In Spain, however, spectacles were popular amongst all classes since they considered eyeglasses made them look more important and dignified.
Far-sighted or aging colonial Americans imported spectacles from Europe. Spectacles were primarily for the affluent and literate colonists, who required a valuable and precious appliance. Benjamin Franklin in the 1780s developed the bifocals. Bifocal lenses advanced little in the first half of the 19th century. The terms bifocal and trifocal were introduced in London by John Isaac Hawkins, whose trifocals were patented in 1827. In 1884 B. M. Hanna was granted patents on two forms of bifocals which become commercially standardized as the "cemented" and "perfection" bifocals. Both had the serious faults of ugly appearance, fragility, and dirt-collection at the dividing line. At the end of the 19th century the two sections of the lens were fused instead of cemented At the turn of the 20th century, there was a considerable increase in the use of bifocals.
Plate illustrating opticians' tools and the products of their work, including spectacles and a spyglass
Between 1781 and 1789, silver spectacles with sliding extension temples were being fabricated in France; however it was not until the 19th century that they gained extensive popularity. John McAllister of Philadelphia began fabricating spectacles with sliding temples containing looped ends which were much easier to use with the then-popular wigs. The loops supplement the inadequacy of stability, by allowing the addition of a cord or ribbon which could be tied behind the head, thus holding the eyeglasses firmly in place.
In 1826, William Beecher moved to Massachusetts from Connecticut to establish a jewellery-optical manufacturing shop. The first ophthalmic pieces he fabricated were silver spectacles, which were later followed by blue steel. In 1869 the American Optical Company was incorporated and acquired the holdings of William Beecher. In 1849 J. J. Bausch immigrated to the United States from Germany. He had already served an apprenticeship as an optician in his native land and had found work in Berne. His reimbursement for the labor on a complete pair of spectacles was equal to six cents. Mr. Bausch encountered difficult times in America from 1849 until 1861, at which time war broke out. When the war prevented import of eyeglass frames, demand for his hard rubber frames skyrocketed. Continuous expansion followed and the large Bausch and Lomb Company was formed.
The monocle, which was first called an "eye-ring", was initially introduced in England in the early 19th century; although it had been developed in Germany during the 18th century. A young Austrian named Johann Friedrich Voigtländer[de] studied optics in London and took the monocle idea back to Germany with him. He started making monocles in Vienna about 1814 and the fashion spread and took particularly strong roots in Germany and in Russia. The first monocle wearers were upper-class gentlemen, which may account for the aura of arrogance the monocle seemed to confer on the wearer. After World War I, the monocle fell into disrepute, its downfall in the allied sphere hastened, no doubt, by its association with the German military.
The lorgnette, two lenses in a frame the user held with a lateral handle, was another 18th-century development (by Englishman George Adams). The lorgnette almost certainly developed from the scissors-glass, which was a double eyeglass on a handle. Given that the two branches of the handle came together under the nose and looked as if they were about to cut it off, they were known as binocles-ciseaux or scissors glasses. The English altered the size and form of the scissors-glasses and produced the lorgnette. The frame and handle were often artistically embellished, given that they were used mostly by women and more often as a piece of jewellery than as a visual aid. The lorgnette maintained its popularity with ladies of fashion, who chose not to wear spectacles. The lorgnette maintained its popularity to the end of the 19th century.
Pince-nez are believed to have appeared in the 1840s, but in the latter part of the century there was a great upsurge in the popularity of the pince-nez for both men and women. Gentlemen wore any style which suited them—heavy or delicate, round, or oval, straight, or drooping—usually on a ribbon, cord, or chain about the neck or attached to the lapel. Ladies more often than not wore the oval rimless style on a fine gold chain which could be reeled automatically into a button-size eyeglass holder pinned to the dress. Whatever the disadvantage of the pince-nez, it was convenient.
In the 19th century, the responsibility of choosing the correct lens lay, as it always had, with the customer. Even when the optician was asked to choose, it was often on a rather casual basis. Spectacles were still available from travelling salesmen.
Spectacles with round lenses (like Winston Churchill), oval shape, panto shape, and tortoise shell frames became the fashion around 1930. The round spectacles and the pince-nez continued to be worn in the 30. In the 40s there was increased emphasis on style in glasses with a variety of spectacles available. Meta Rosenthal wrote in 1938 that the pince-nez was still being worn by dowagers, headwaiters, old men, and a few others. The monocle was worn by only a minority in the United States. Sunglasses, however, became very popular in the late '30s.
Equipment
Opticians use a variety of equipment to fit, adjust and dispense eyewear, contact lenses, and low-vision aids.
Manual lensmeter
Technically identified by the generic term manual lensmeter, opticians may often refer to this piece of equipment as a lensometer, focimeter, or vertometer. The modern lensmeter was invented in 1922 by Edgar Derry Tillyer of American Optical to determine "whether lenses have the refraction and power prescribed."[9] Proper use of the lensometer by a dispensing optician or a lab optician includes verifying back or front vertex power, orientating uncut lenses for finishing and glazing, and confirming the mounting of lenses into the frame.[10] Manual lensmeters can also be outfitted with an attachment to read the back vertex power of a contact lens for modification and verification purposes.[11]
The optician uses the refracted, or bent light, displayed within a lensmeter to interpret the sphere, cylinder, and add powers (if prescribed), axis orientation, prismatic effect, and locate the major reference point of the lens.[12] Correct interpretation of these readings is critical to the performance of the eyewear and user satisfaction.
Automated lensmeter
An automated lensmeter uses the reflected wavelength of green light off of the lens surface along every lens meridian in order to determine all of the data points that the optician interprets with the manual lensometer. The benefits of an automated lensmeter are increased speed, adjustments for variables in the index of refraction in the lens material, the ability to measure UV and light transmittance, and a decrease in training time while on the job. The drawbacks of automated lensmeters in comparison to manual lensmeters are greater difficulty identifying higher prismatic errors, aberrations, and surfacing power errors (optic waves), and the necessity of the optician not to tip the lens to avoid an erroneous result.[13]
Corneal reflex pupilometer
A corneal reflex pupilometer is a digital device used to measure Interpupillary Distance (IPD), otherwise known as Pupillary Distance (PD). The measurement is used to align the Major Reference Point (MRP) of the lenses along the visual axis to reduce unwanted prismatic effect, eyestrain, and lens aberrations.[14]
A PD can be taken Binocularly (from the corneal reflex of one pupil to the corneal reflex of the other) or Monocularly (from the center of the spectacle bridge to the center of the corneal reflex of each eye independently with the non-measured eye being occluded). By providing a rest point on the bridge similar to an eyeglass frame, pupilometers provided a proper reference point for obtaining an accurate monocular PD value.[15]
PDs are also taken in relation to focus point. The eyes can be focused at infinity (distance), focused near (approximately 16 inches or 40 centimeters), or intermediate (a working distance in between near and distance.[16] Because a pupilometer can be dialed to a specific distance and easily occluded, it is often easier to work with. This does not mean that it is more accurate than a skilled optician with a corneal reflex light, a millimeter ruler called a PD stick, and fully adjusted eyewear for certain age groups and pathologies. While a ruler alone is susceptible to parallax error, when it is used in conjunction with the other tools previously mentioned the accuracy can exceed the pupilometer for these certain patient groups [17]
The fitting and dispensing of contact lenses requires the use of additional equipment, all with very specific purposes. A keratometer is a diagnostic instrument for measuring the curvature of the anterior surface of the cornea, particularly for assessing the extent and axis of astigmatism. It was invented by the French ophthalmologist Samuel Hankins in 1880. Opticians, like ophthalmologists and optometrists, also use a slit-lamp/bio-microscope to examine the anterior segment, or frontal structures and posterior segment, of the human eye, which includes the eyelid, sclera, conjunctiva, iris, natural crystalline lens, and cornea. The binocular slit-lamp examination provides stereoscopic magnified view of the eye structures in detail, enabling anatomical diagnoses to be made for a variety of eye conditions.
While a patient is seated in the examination chair, he rests his chin and forehead on a support to steady the head. Using the biomicroscope, the optician then proceeds to examine the patient's eye. A fine strip of paper, stained with fluorescein, a fluorescent dye, may be touched to the side of the eye; this stains the tear film on the surface of the eye to aid examination. The dye is naturally rinsed out of the eye by tears. Adults need no special preparation for the test; however children may need some preparation, depending on age, previous experiences, and level of trust.
The list of equipment used by an optician is extensive and is often specified in jurisdiction specific Professional Standards of Practice.[18] The standards of the College of Opticians of British Columbia serve as an example.
By country
Canada
All provinces in Canada require opticians to complete formal training and education in opticianry and then must pass competency examinations prior to receiving governmental licensure. Some provinces (Ontario and Quebec) require a single optician's license that includes both the dispensing of eyeglasses and contact lenses, while the other provinces have two separate licenses, one each for eyeglasses and contact lens dispensing.
Recent changes to the British Columbia Opticians regulations allow qualified opticians in that province to test a person's vision and prepare an assessment of the corrective lenses required for a client. Using the results of the assessment an optician is able to prepare and dispense eyeglasses or contact lenses. Opticians in Alberta and Ontario are also permitted, under certain conditions, to refract and prepare and dispense eyeglasses and contact lenses.
Provincial regulatory organizations
Each Canadian province has its own regulatory College or Board that provides registration or licensure to its opticians. The Regulatory body (often known as a ‘College’ but separate from, and not to be confused with, an educational institute) has a government mandate to protect the public. This includes enforcement of provincial statutes (Opticians Act) and public awareness campaigns.
The National Association of Canadian Opticianry Regulators (NACOR)
The National Association of Canadian Opticianry Regulators (NACOR) is an organization of all the provincial opticianry regulatory bodies in Canada (except Quebec). NACOR also administers Canada's national opticianry examination(s). Since 2001, all jurisdictions (except Quebec) have agreed to and signed, the Mutual Recognition Agreement among Opticianry Regulators that ensures labour mobility to all opticians across the entire nation without need for further examination. All provinces (with the exception of Quebec) require individuals to achieve a passing mark in a national examination as a requirement of licensure as an optician.
Despite the non participation of Quebec in National initiatives, Canadian opticians who relocate to Quebec are able to register and practice in that province provided they meet certain language requirements.
Provincial associations
Most Canadian provinces have their own provincial opticianry associations that look after the interests of their members at the provincial level, such as advocacy. Some provincial regulatory agencies have a dual role or purpose and also serve as the association for that province. In addition to protecting their member's interests, provincial associations also undertake public interest initiatives such as providing vision screening for children in schools, or organizing professional development seminars.
Established in 1989, the Opticians Association of Canada is a national organization of all provincial Opticianry Associations in Canada. The role of the OAC is to advocate for the various interests of opticians on a national basis.
Education
As a prerequisite for registration in any province of Canada opticians are required to complete a course at one of the NACOR accredited teaching institutions. Persons from an international jurisdiction may apply to a provincial regulatory agency for an assessment of equivalency of their education. Such applications are not unreasonably denied.
Nigeria
Dispensing Opticians are regulated by the Optometrists and Dispensing Opticians Registration Board of Nigeria (ODORBN). The training programme is a 3-year diploma programme in a Board accredited institution, located in all geopolitical zones of the nation. Some of the training institutions are Kwara State College of Health Technology (Offa), Federal Polytechnic (Nekede), Millennium College of Health technology.
United Kingdom
Opticians or Dispensing Opticians are regulated by the General Optical Council (GOC). A dispensing optician advises on, fits and supplies the most appropriate spectacles after taking account of each patient's visual, lifestyle and vocational needs. Dispensing opticians also play an important role in fitting contact lenses and advising and dispensing low vision aids to those who are partially sighted and in advising on and dispensing to children where appropriate.
The Association of British Dispensing Opticians (ABDO) is the qualifying body for dispensing opticians in the United Kingdom (UK). The Fellow of British Dispensing Opticians (FBDO) is the base qualification for UK dispensing opticians. This qualification has been awarded level 6 status (equivalent to BSc) by Ofqual Welsh Assembly Government and Council for Curriculum Examinations and Assessment (CCEA). Additional qualifications, Contact Lenses and Low Vision have been assessed at level 7 (equivalent to an MSc).
United States
In the United States, an optician, through testing, may be certified by the American Board of Opticianry (ABO) to fill the prescription ordered by an ophthalmologist or optometrist. Note: The ABO Exam is not nationally recognized and does not indicate a license to practice as an optician. In roughly half the states,[which?] licensing is not a requirement to make or dispense eyewear. Many eye doctors do their own dispensing, and it is frequent for eye clinics to have an optician on their premises; or, conversely, for large optical chains to have optometrists in offices on their premises.
Some opticians learn their skills through formal training programs. Professional technical schools and two-year colleges offer programs in opticianry. Two-year programs usually grant an associate degree. One-year programs offer a certificate. Training usually includes courses in optical math, optical physics, and tools and equipment use. Other opticians can apprentice to learn the required skills. Many formal education programs will accept hours worked as an apprentice to supplement or replace course credits, as well.
United States Organizations That Impact Opticianry on a National Level
A corrective lens is a transmissive optical device that is worn on the eye to improve visual perception. The most common use is to treat refractive errors: myopia, hypermetropia, astigmatism, and presbyopia. Glasses or "spectacles" are worn on the face a short distance in front of the eye. Contact lenses are worn directly on the surface of the eye. Intraocular lenses are surgically implanted most commonly after cataract removal but can be used for purely refractive purposes.
Glasses, also known as eyeglasses and spectacles, are vision eyewear with clear or tinted lenses mounted in a frame that holds them in front of a person's eyes, typically utilizing a bridge over the nose and hinged arms, known as temples or temple pieces that rest over the ears.
Bifocals are eyeglasses with two distinct optical powers. Bifocals are commonly prescribed to people with presbyopia who also require a correction for myopia, hyperopia, and/or astigmatism.
Optometry is a specialized health care profession that involves examining the eyes and related structures for defects or abnormalities. Optometrists are health care professionals who typically provide comprehensive eye care.
Pince-nez is a style of glasses, popular in the late 19th and early 20th centuries, that are supported without earpieces, by pinching the bridge of the nose. The name comes from French pincer, "to pinch", and nez, "nose".
An eyeglass prescription is an order written by an eyewear prescriber, such as an optometrist, that specifies the value of all parameters the prescriber has deemed necessary to construct and/or dispense corrective lenses appropriate for a patient. If an eye examination indicates that corrective lenses are appropriate, the prescriber generally provides the patient with an eyewear prescription at the conclusion of the exam.
Progressive lenses are corrective lenses used in eyeglasses to correct presbyopia and other disorders of accommodation. They are characterised by a gradient of increasing lens power, added to the wearer's correction for the other refractive errors. The gradient starts at the wearer's distance prescription at the top of the lens and reaches a maximum addition power, or the full reading addition, at the bottom of the lens. The length of the progressive power gradient on the lens surface depends on the design of the lens, with a final addition power between 0.75 and 3.50 dioptres. The addition value prescribed depends on the level of presbyopia of the patient. In general the older the patient, the higher the addition. They are also known as multifocal lenses, progressive addition lenses (PAL), varifocal lenses, progressive power lenses, graduated prescription lenses, or progressive spectacle lenses.
Rodenstock GmbH is a German manufacturer of ophthalmic lenses and frames for eyeglasses. The company, which was founded by Thuringian Josef Rodenstock in 1877, is headquartered in Munich.
A lorgnette is a pair of spectacles with a handle, used to hold them in place, rather than fitting over the ears or nose. The word lorgnette is derived from the French lorgner, to take a sidelong look at, and Middle French, from lorgne, squinting. Their precise origin is debated: some sources describe English scientist George Adams the elder as their inventor, while others cite his son George Adams the younger.
An optometrist is an individual who provides a service related to the eyes or vision. It is any healthcare worker involved in eye care, from one with a small amount of post-secondary training to practitioners with a doctoral level of education.
Pupillary distance (PD), more correctly known as interpupillary distance (IPD) is the distance in millimeters between the centers of each pupil.
Williamson v. Lee Optical Co., 348 U.S. 483 (1955), was a case in which the Supreme Court of the United States held that state laws regulating business are subject to only rational basis review and that the Court need not contemplate all possible reasons for legislation.
A lensmeter or lensometer (sometimes even known as focimeter or vertometer), is an optical instrument used in ophthalmology. It is mainly used by optometrists and opticians to measure the back or front vertex power of a spectacle lens and verify the correct prescription in a pair of eyeglasses, to properly orient and mark uncut lenses, and to confirm the correct mounting of lenses in spectacle frames. Lensmeters can also verify the power of contact lenses, if a special lens support is used.
Adjustable focus eyeglasses are eyeglasses with an adjustable focal length. They compensate for refractive errors by providing variable focusing, allowing users to adjust them for desired distance or prescription, or both.
Vision of humans and other organisms depends on several organs such as the lens of the eye, and any vision correcting devices, which use optics to focus the image.
Rimless eyeglasses are a type of eyeglasses in which the lenses are mounted directly to the bridge or temples. The style is divided into two subtypes: three-piece glasses are composed of lenses mounted to a bridge and two separate temple arms, while rimways feature a supporting arch that connects the temples to the bridge and provides extra stability for the lenses.
Frames Direct is an international online eyewear retailer. The company sells eyewear products such as eyeglasses, prescription sunglasses, sunglasses, and contact lenses through its website, https://www.framesdirect.com. Frames Direct sells designer and brand-name eyewear products with over 50,000 models. Founded in 1996, Frames Direct was one of the earliest online optical retail stores and the first to sell prescription sunglasses online.
Eye care in the United Kingdom is available through the National Health Service. Eye care in the community is almost entirely provided by optometrists in private practice. Specialist NHS services are provided from a small number of eye hospitals, and their staff often run clinics in general hospitals in their region.
Dean Evan Hart, O.D., M.A., M.S., B.S., A.A.S., F.A.A.O. is an American scientist, clinical optometrist, professor, and the founder of Woodbury Ophthalmic Group and Woodbury Optical Studio. Dean ran for Nassau County Legislature in 2015. He was a candidate for the New York State Assembly in the 15th Assembly District of the 2016 election. Hart also ran for town office in 2017.
Visibly, formerly known as Opternative, is a telehealth Chicago-based company which provides on-line vision tests and generates eyeglasses and contact lens prescriptions.
↑ “Tillyer, ’02, A Leader in his Field,” Rutgers Alumni Monthly (May 1922): 220.
↑ Sheedy, James E. "Essentials of Ophthalmic Lens Finishing." (2004): 397.
↑ Kollbaum, Pete, et al. "Validation of an off-eye contact lens Shack-Hartmann wavefront aberrometer." Optometry and vision science: official publication of the American Academy of Optometry 85.9 (2008): E817.
↑ ANSI Z80.1-2020. Ophthalmics-Prescription Spectacle Lenses. ANSI Electronic Standards Store
↑ Atebara, Neal H., David Miller and Edmond H. Thall. Ophthalmology, 2.5, 56-67.e1
↑ Brooks, Clifford and Borisch, Irving. Systems for Ophthalmic Dispensing, Third Ed. Stoneham, MA.: Butterworths, 2007
↑ Santini, Barry. "Meet Your Pupilometer". 20/20 Magazine, January 2021. p.64
↑ Brooks, Clifford and Borisch, Irving. Systems for Ophthalmic Dispensing, Third Ed. Stoneham, MA.: Butterworths, 2007
↑ Keirl, A., (2010), Paediatric Eyecare – part two, Anthropometry and Spectacles Frames for Children, Dispensing Optics, 25,10.
↑ Standards of Practice of the College of Opticians of British Columbia and Ontario
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