How much do sunglasses weigh
The weight of the sunglasses are normally not the same, basically they are depends on the materials they are used. And different materials have their own advantages and disadvantages. Normally the glass sheet is heavier than the resin sheet, and if your lenses have higher power degree, it will weigh much heavier. Also we need to consider about the refraction index of the lenses. The temples and frames are very different, they all have impact for the weight of the sunglasses. Normally a pair of sunglasses will not weigh over than 40g.Metal frame plus lenses should be within 20g, and the normal plate frame plus the lenses will weigh around 20g, TR90 frame plus the the lenses will normally weigh 12-14g, and the titanium frame with lenses is about 14g. But many people would ask, if I should choose the heavy or light? Actually, if you choose the heavy frame, the materials are sufficient and solid. It will not be easy to damage. However, for most of the sunglasses lovers, they are also sports lovers, so the light weighted sunglasses may be appropriate. Because we want to have a comfortable feeling while wearing a sunglasses because we need them for a long time. Especially in summer, the light weighted sunglasses are more popular.
The full rims, semi-rims and the No-Rim frames
The frame is an important part of spectacle frame, which mainly supports the spectacle lens. The spectacle frame with beautiful appearance can also create a beautiful image for you. The Materials for the sunglasses mainly include metal, plastic or resin, natural materials, etc. According to different styles, the sunglasses can be divided into full-rim frame, Semi-rim frame, No-Rim frame and other types. A pair of spectacle frame is usually composed of a lenses ring, a nose bracket, a pile head, temples and other main parts. In addition to the above mentioned parts, there are foot cover, bracket screw, hinge screw and so on. Of course the No Rim should be the lightest, however, although it looks beautiful, but it is not safe to wear it, which is easy to damage, and it is hard to have a good protection for your eyes. The semi rims are also light weighted, but comparing with the full rim sunglasses, they are less safer.
The materials of the sunglasses:
1. White copper mirror frame (copper zinc alloy): the main components includes 64% copper, 18% zinc and 18% nickel. The mirror frame material is the cheapest and easy to process. Electroplating is mainly used for making hinge wire, small parts and low-grade mirror frame.
2. High nickel alloy frame: the nickel content is more than 80%, mainly including nickel chromium alloy, manganese nickel alloy, etc. the corrosion resistance of high nickel alloy is better, in addition, the elasticity of the material is good.
3. Monel material frame: nickel copper alloy, with nickel content of 63% and copper content of about 28%. In addition, there are a small amount of iron, manganese and other metals, especially corrosion resistance, high strength and firm welding. It is the most widely used material for mid range frame.
4. Pure titanium mirror frame: the specific gravity of titanium is only 4.5, which is very corrosion-resistant, and its strength is twice that of steel. It is used to manufacture the watch case of space shuttle, and is called “space metal”, and there is no metal allergy problem. The advantages of this materials is light weighted.
If the refractive index is higher, the lenses will be thinner, but please note that this is a raw lens.
For a pair of glasses, the priority is the degree. A pair of 1.50 refractive index 100 degree lens is thinner than a pair of 1.74 refractive index 600 degree lens. In addition, the selection of frame and lens will also be related.
The choices for the weight of sunglasses
For the selection of frames type, full-rim > semi-rimless > rimless. Frameless will make the edge thickness of the lens exposed in front of others. And the frame is easy to deform, resulting in the change of the center distance and astigmatism axis of the glasses, which affects the correction effect. The full-rim and semi-rimless are better than the rimless because the full-frame can wrap the lens, so it won’t appear that the lens is too thick.
Don’t choose a frame or a frame with too thin legs. In this way, it will appear that the lenses are relatively heavy, especially the legs are too thin, and the force on the front and back of the frame is not balanced, so it is easy to put most of the weight on the bridge of the nose, which will cause the glasses to slide down easily and affect the wearing comfort.