Testing of aspheric lens
The optical axis of the optical center just overlaps with the visual axis of the eye, which is the most ideal state. Because the light from the edge cannot form a focus on the optical axis, when the optical axis does not overlap with the visual axis (the difference is greater than 2mm), such unclear and scattered imaging results will occur. When choosing frames and aspheric lenses, you need to ensure that they fit correctly, to achieve the best visual and decorative effects. Simply put, due to the special design of the lens, we found through a calculation that the optical center should move down 1mm higher than the pupil for every 2° increase in front inclination angle. Otherwise, the wrong pupil height will cause the lens to look like astigmatism, and cause discomfort. For glasses with aspheric lenses, there must be an inclination angle after wearing. The specific angle varies from person to person.
Sunglasses For Fishing - Ray-Ban
Ray-Ban was founded in 1930 in the United States. It is the inventor of the world's first sunglasses and is known across the world for it. It is treated as a symbol of American culture. ?Since its inception, Ray-Ban has been focusing on the development of sun-blocking products and integrating a lot of high-tech into them, committed to providing the best vision protection for modern consumers.
Wrapped in a rich, multicolored opaque pattern in creamy pale pink, Joanie Reading Glasses features a square frame that is a statement of personality. As part of Foster Grant's Modera series, these frames give your makeup just the right amount of color and gloss. The spring-hinged temple provides a comfortable feel suitable for all-day wear.
5 Unbreakable Eyeglasses Frames
In this section, we will list the most durable eyeglasses frames and we will introduce them one by one.
Titanium: One of the most durable eyeglasses frames is the titanium eyeglasses frames. It is lightweight, strong, and flexible. So, titanium eyeglasses frames have lots of fans in the eyeglasses market. In addition, pure titanium is hypoallergenic. But, due to these features, titanium eyeglasses frames are expensive than other frames.
Stainless steel: Stainless steel frames have some spring in them, which resists breakage. Stainless steel also resists corrosion, giving it a longer life. However, stainless steel eyeglasses frames may be hypoallergenic, depending on the alloys used.
Nylon: many people like athletes like nylon frames because they are flexible, lightweight and unbreakable - at least in the short run. However, nylon frames may become brittle over time, which is something to think about.
Kevlar: kevlar eyeglasses frames used in bulletproof vests can survive strong impacts, making them a good choice for contact sports and high-risk jobs. It does not have a lot of flex, limiting its applications.
Flexon: besides the above unbreakable eyeglasses frame, we will introduce another brand-name metal - Flexon. Flexon has a unique capability for springing back to its original shape after it gets twisted and they are called memory metal.
Difference Between Driving Glasses And Night Vision Goggles
The use of driving glasses and night vision glasses is different. When sunlight is projected on the road or water, it directly stimulates the eyes, making them feel dizzy, tired, and unable to see for a long time. Especially when you are driving a car, doing outdoor entertainment activities, it will not only affect our work and entertainment mood, and even affect our judgment of the image and cause danger. The polarized driving glasses can be used during driving, fishing, skiing, rain, etc. when there is a strong reflection of strong light. Night vision goggles are usually used at night and have great applications in transportation, the military, and other fields. A large amount of night vision equipment has been used as a winning strategy to dominate night combat. Combining night vision technology with weapons and equipment will greatly improve the effectiveness of weapons and equipment in getting information, conducting strikes, commanding troops, and coordinating operations at night and in bad weather.
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.
How to buy anti-blue light products?
In order to further standardize anti-blue light products and make all kinds of products effectively protect eye health, relevant standards have been formulated. Based on the different effects of blue light in different bands on the human body, the transmittance of blue light in each band is required in the standards.
For example, in the band range of 415-445 nm, the transmission ratio of light is less than or equal to 80%, and more than 445 nm, it is greater than 80%.