Lens Types
It is essential that all people have a basic understanding of lenses. Eventually, all people will need reading glasses if they do not need glasses from the very beginning of their life. The user needs to have a general knowledge of what is available and the different characteristics of some basic lens types. Also, the understanding of one’s own needs is necessary to avoid being steered into a more lucrative sale for the commission paid optician. Eyeglass lenses are one of the many different types of lenses. The lenses used in eyeglasses can fit into a few specific categories such as: single vision, bifocal, trifocal and progressive types.
As an optical lab manager and technician for the last 15 years, I see and use these various types of lenses daily to fill the prescriptions and needs of the user. The position of lab manager also gives me the specific knowledge of the remakes produced that are generated by opticians more interested in selling what they make the most commission or get the greatest kick backs from. It is these influences that make it imperative that the user of the glasses has an understanding of how each lens type could affect the usefulness of how the glasses are used in his or her individual activity.
Lenses are broken into two main categories: single vision and multifocal. Single vision lenses are used to correct focal point problems within the eye, as well as distortion problems. To accomplish this task, single vision lenses are categorized into spherical power lens and lenses that also have cylinder correction. Most end up being a combination of both focal point and distortion correction. Spherical lenses are broken down further into plus and minus correction depending on whether the patie...
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...r years will, at some point, need glasses for correction of their near vision. This is accomplished with any of the single vision, bifocal, trifocal or progressive types. All these lens types have specific purposes and reasons for their use with advantages and shortcomings for each design and purpose. It is important that the user understand his or her options to make a wise selection to fulfill his or her needs the best. The user cannot always assume the optician or salesperson has a full understanding of the specific user’s requirement when a commission or kickback is involved. With this fact in mind, it is always best if the user has a basic understanding of the different lens types available.
Reference
The Eye Info Network. (2011). Choosing eyeglass lenses. Retrieved from All About Eyeglasses website: http://www.allabouteyeglasses.com/eyeglass_lenses.htm
Optometrists have accepted vision therapy, which is a medical treatment for optical muscle disabilities, as a feasible treatment used for eye related problems; claiming the treatment can strengthen vision and give the patient the opportunity to understand visuals quicker and clearer (Press). Vision therapy originated in the 1950s and over the past 25 years, has gained popularity, mainly because of new technological innovations in the field of treatment. Generally, vision therapy is prescribed as a measure mainly for people between the ages of 3 and 18. With the results from a comprehensive series of eye tests, the optometrist can work with the patient using special instruments—prisms, filters, occluders, and eye lenses—and strengthen the eye muscles, thus improving sight. According to optometrists in favor of vision therapy, these methods of treatment using these instruments function as safer routes to repair eye disabilities. Although vision therapy can yield favorable results, the practice as a treatment for innate eye disabilities has been in hot debate lately; as it can exceed $8000 and insurance companies do not cover the treatment. For decades, insurance companies have refused to accept vision therapy as a legitimate method for repairing eyesight (Boink). Concomitant with lack of insurance, the cost for a full treatment can exceed $8000, and doctors cannot guarantee a successful outcome. Recently, parents of children with eye related disabilities, such as amblyopia (lazy eye) and strabismus (cross-eye), and doctors have attempted to cooperate with public schools to allow families access to school-funded doctors to practice vision therapy. With a tight budget, most schools cannot afford to supply vision therapy, and a...
My interest in the career of optometry stems from my first experience in the optometry office to receive my first pair of glasses when I was in middle school. I distinctly remember the moment when my optometrist slipped my new glasses over my eyes for the first time. Suddenly, everything in the room came into sharp, clear focus. I knew that the glasses would help me see the board in school, but I was astonished to find that I could see small details about the room, as it had never before occurred to me that I should have been able to see these details. I was also surprised that I was even able to see the expressions on the faces of people who were standing far away from me. It was one of the most incredible, freeing, and empowering moments of my life. As I walked out of the optometry office, I felt
Benton, Michael. “Benjamin Franklin Bifocals” Benjamin Franklin Venturio Media, 6 November. 2013. Web. 11 December. 2013.
You can find almost any glasses you want in the market, like well known big brand glasses, or glasses with reasonable price, or several pairs for cheap price in online as well as in stores. But the question is can you find prescription glasses with good quality, good price and plus fashionable? Even though competition is very high, Warby Parker has strong competitive advantage. Warby Parker design differentiate from others by its unique vintage style, color specifically tailored for urban young generation. Also Warby Parker can offer a cheap price for good quality eyeglasses, because they manufacture eyeglasses themselves and there is no middle man cost.
As humans age, they frequently develop a condition known as presbyopia. This condition decreases the person's ability to focus sharply on those object which are nearby and is the result of the lens of the eye hardening. In addition, astigmatism requires a person wear prescription eyeglasses and/or contact lenses. Astigmatism arises when the curvature of the eye is irregular. The eye is normally shaped liked a soccer ball or basketball. With astigmatism, it takes on a more oval shape and resembles a football. Due to the irregular curvature, the eye processes light differently and leads to blurred vision. The degree of blurriness is determined by the degree of
Eyes are the ‘organ of sight or vision; the visual sense; the sense of seeing’ (Biology-Online). The eye is an organ that detects light and sends signals along the optic nerve to the brain. The eye allows for light recognition and the ability to differentiate between colors, and light and dark. The eye is approximately 2.54 cm wide, 2.54 cm deep and 2.2 cm tall. The human eye has around 200-degree viewing angle and can see and detect more than 10 million colors and shades. This essay is going to look at ways of seeing. The possible problems with eyesight, and eyes of various kinds. It is one of the most rare problems today that is affecting people, all over the world. Around the world an estimate of 4 in 10 people have perfect vision/sight (BBC). The population of the world right now
No, not "Why am I going to class so early?" but "Why do I need these contacts?" With this project I will attempt to explain the basics of vision and corrective lenses, as I, myself, finally learn the reason for sticking my finger in my eye every morning.
The principle behind the refractive telescopes is the use of two glass lenses (objective lens and eyepiece lens) to gather and bend parallel light rays in a certain way so that the image fits the size of the eye's pupil. Light rays is gather through the opening of the telescope called the aperture and passes through the objective lens and refracts onto a single point called the focal point. From there the light rays continue the same direction until it hits the eyepiece lens which also refract the light back into parallel rays. During the process, the image that enters our eyes is actually reverse of the original image and magnified because the size in which we preceive the image.
"Trifocal Glasses Lenses,."Trifocal Lenses,. Eyeglass Lens Direct, 1 Jan. 2014. Web. 23 May 2014. .
Optometrists are experts specializing in vision care. They perform eye testing to identify irregularities or diseases of the eyes. They're also masters in the use of eye glasses as well as contact lenses to fix distinct vision ailments. Additionally, they review the condition of both eyes to find out what triggers a patient's vision trouble.
When the contact lens was invented, the world of vision correction was altered forever. No longer were those people lacking perfect 20/20 vision forced to look any different than everyone else. Both discrete and revolutionary, the contact lens provided a brand new, viable, alternate solution to an age-old problem. After centuries of engineering and discovery the contact lens has evolved greatly. Presently contact lenses are made hard or soft, for daily or continuous wear, gas permeable, and even providing ultraviolet protection. A properly fitted pair of today’s discrete, convenient, versatile, and inexpensive contact lenses provide the best form of vision correction available in today’s market.
“A dispensing optician’s role entails, advising on, fits, supplying, and recommending the most appropriate spectacles after taking into account a patient’s visual, lifestyle and vocational needs”. (https://www.optical.org/en/Education/Careers/Pre-registration_home.cfm)
...he cornea is deformed so that its surface is oval instead of spherical. Light rays are distorted at the entrance of the eye. This produces a blurred image and is known as astigmatism. To correct it, glasses are given a nonspherical or cylindrical curvature. Cross-eyes and walleyes are produced when both eyes do not work together because of weakness of the eye muscles.
The refracting telescope is one of many different types of telescope. Refracting telescopes work by refracting the light through an initial convex lens, (known as the objective lens), then through another convex lens (known as the eyepiece lens). These two lenses focus the light into the eyepiece so we can see the image clearly.