Different types of nose pads for glasses
The fixed nose pad is usually used on the plate frame. The nose pad and the frame form an organic whole. The maintenance is more convenient, unlike the movable type that should often twist a screw. It is not easy to hide dirt and dirt. But the disadvantage is that the angle of the nose pad can not be adjusted, and it can not fit the bridge of the nose greatly. The movable nose pad can be automatically adjusted up and down according to the shape of the bridge of the nose to ensure that the compression part of the bridge of the nose is evenly stressed and the local pressure is reduced. But the disadvantage is to often check the tightness of the screw, but often scrub clean. The silicone material usually used in the nose pad is easy to yellow after a long time, which affects the appearance.
Thickness of lens
The thickness of the driver's glasses affects the use of glasses in a way. The glasses with thicker lenses can be more durable to prevent the glasses from being irritated and accidentally broken, effectively protecting the eyes.
Martinez Eye Associates
Optometrists and the Optometrists Association team are committed to providing the best optometry service. They invite you to visit their website. Martinez Eye Associates is a full-service eye and vision care provider based on personal attention and professional care. They are dedicated to providing the highest quality of eye care from infants to seniors. Online contact lens stores offer very competitive prices. They ship directly from the manufacturer within 3-5 business days. They are committed to providing high-quality optometry services in a comfortable environment.
The design evolution of progressive lenses
Spherical and aspheric designs
The design of the front surface of the far-use area of the early progressive lens is similar to that of the ordinary spherical single vision lenses, so it is called a spherical progressive lens. Since 1974, the front surface of the far-use region of the lens is designed to be aspheric by designers, which not only reduces the peripheral aberration but makes the lens thinner, lighter, and less powerful.
Hard and soft design
For hard design, the channel is short, and the gradient is large. The near-use area position is high. The effective visual area of remote and near-use areas was larger. Peripheral astigmatism is relatively concentrated. Because surrounding astigmatism increases rapidly and the distribution is dense, the curve effect is more obvious. The gradient area is narrow. It is more difficult and takes longer for wearers to adapt.
Lenses with soft designs have slower gradients, longer gradients, and wider gradients. The angle of rotation of the eye from the far area to the near area is greater. It's easier to get used to. Compared with the hard design, the effective visual area of the far and near use areas is smaller, and the location of the near use area is lower.
Single, diverse, and individualized design
Initially, the progressive lenses used a single design, in which each basic curve was scaled equally and a luminosity combination was added within the range of its semi-finished lens blanks. The steepest base curve uses the same lens design as the flattest base curve. Lenses designers quickly realized that the overall performance of the lens could be improved by microcustomizing the lens design, leading to progressive lenses with multiple designs. This kind of design is called diverse design. By the mid-1990s, there was the emergence of individualized lens designs. In addition to using different gradients, these first individualized lens designs used steeper baseline curves with a slightly larger approach area to compensate for increased magnification and reduced field of view.
Symmetrical and asymmetric design
There is no difference between the left and right eyes in the symmetrical design of progressive lenses. As the eyes turn inward when they see near objects, the gradual gradient area gradually tilts to the nasal side from top to bottom, so the left/right progressive lenses should be rotated clockwise/counterclockwise respectively during processing. An asymptotic lens with left and right eye divisions is called an asymmetric design. The gradient is gradually and moderately inclined to the nasal side from top to bottom. The refractive force, astigmatism, and vertical prism of the two sides of the left and right gradient of the asymmetric design lenses are basically similar. At the same time, considering the characteristics of eye movement parameters in binocular vision, the peripheral aberrations of the corresponding positions of the left and right lenses were appropriately balanced to improve the visual effect of the wearer.
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Ordinary glasses frames are easy to break and rust, so we always have to replace glasses frequently. Pure titanium spectacle frames are made of 'space metal' aviation materials, and strive to accompany your growth with each pair of pure titanium spectacle frames, witness every moment of your happiness, anger, sorrow, and joy. Let pure titanium spectacles become your personal little guard and the doorman for the window of the soul.
What is the cheapest way to buy prescription glasses?
Optometry must be accurate. Optometry is the main basis for glasses. The accuracy of optometry is directly related to the success rate of the glasses prepared. Optometry must be accurate first, and the difference between the upper and lower levels should not exceed 12.5 degrees of the prescription. Secondly, the astigmatism axis should be accurate, and the general axis difference should be limited to plus or minus l to 3 degrees. In addition, the interpupillary distance must be accurate, and the interpupillary distance must be equal to the optical center distance of the lens. If you do not pay attention to the above-mentioned checkpoints in optometry, the prepared spectacle lenses will have blurred vision, prolonged visual fatigue, dizziness, nausea, and even diplopia. Optometry is best to go to a professional eye hospital. For children’s optometry or to wear glasses for the first time, you must use mydriatic optometry to be accurate. You can also check if there is any problem with the fundus, and go to the hospital to get more accurate optometry.
Round Glasses
While round glasses have been popular for the past few years, this season, metallic round frames from the '80s and 90s are getting more attention. These days, round glasses aren't just for Harry Potter fans. People add a sense of weirdness or fashion to their appearance. If you have an angular face and a chiseled chin, then round glasses are for you.
