loading

A professional manufacturer of measuring & testing equipment.

Over several centuries elapsed since the real

Single vision optical eye wear are the first and most widely used products in the field now. The first real eyeglass wear invented several hundreds of years ago were almost all single-vision, and they were used as vision rectifying devices in most cases. These eyeglasses also take the largest market share in present market. This is firmly related to the features of these glasses. These eye glasses are mainly designed single vision, which is particularly effective in solving some simple eye problems, from which most people are now suffering. In other words, single vision optical eye wear are designed professionally for single vision related eye problems, like nearsightedness, farsightedness and other common vision errors.

Multi-focal optical eye wear are specially made for people who are in need of special prescription eyeglasses. Though most eye problems people suffering in their daily lives can be ideally treated with single vision glasses, there are some unique eye diseases that can not be rectified by them, like presbyopia, an age related problem. Therefore, it is needed to create some professional optical eyeglasses- multi-focal eyeglasses. These eye wear have a least two vision focal on each lens. And the firstly multi-focal glasses, namely, bifocals, were said to be invented by Benjamin Franklin in the 18th century. Later, technologies and techniques in the field advance rapidly, multi-focal glasses in other forms arise on and on, like trifocal eyeglasses, progressive eyeglasses, etc. All these above mentioned eye wear are very popular among wearers with both nearby and far vision problems.

Of course, much greater achievements will made in the aforesaid two optical eyeglasses as some related technologies and techniques advance rapidly. And it can be said safely that these eye wear will become more and more professional in their functionality in the future and people with particular vision problems can benefit greatly from them as a result.

GET IN TOUCH WITH Us
recommended articles
200 FAQs WHAT' S NEW APPLICATION
How to keep the hydraulic universal testing machine clean



Hydraulic universal testing machines have very high accuracy requirements.
Connection of hydraulic system of tensile testing machine



The hydraulic system is the power drive mechanism of the tensile testing machine.
Application of electronic universal testing machine in automobile industry



The specific application of the electronic universal testing machine in the automobile manufacturing process: The electronic universal testing machine needs to be used for automobile parts.
Wave soldering workflow



Wave soldering refers to the molten solder (lead-tin alloy), sprayed by electric pump or electromagnetic pump into the solder wave required by the design, can also be formed by injecting nitrogen into the solder pool, so that it is pre-loaded The printed board of the component realizes the soft soldering of the mechanical and electrical connection between the solder end or the pin of the component and the pad of the printed board through the solder wave.
Protection of frequency converter of hydraulic universal testing machine



The frequency converter is a power control equipment that uses frequency conversion technology and microelectronics technology to control AC motors by changing the frequency of the motor's working power supply.
Common failures of electronic universal testing machine



Electronic universal testing machine is a necessary equipment to control the quality of products.
Calibration method of electronic universal testing machine



The calibration operation of the electronic universal testing machine is still relatively unfamiliar to friends who use it for the first time.
Brief introduction of selective wave soldering defects and prevention



Selective wave soldering defects and their prevention.
Some precautions when using the testing machine



Testing machine, broadly speaking, is an instrument that verifies the quality or performance of a product or material according to the design requirements before it is put into use.
How to measure the tensile force of the testing machine



The tensile force is not an accurate value after being measured by the testing machine, and subsequent calculations are required to get the desired value.
no data

  Tel: 0086-0769-2318 4144

  Mobile: 0086-137 2828 8444

no data
CONTACT US

Copyright © 2025 Sinowon | All Rights Reserved.

Customer service
detect