Progressive glasses can be used to see far, medium and near distances with one pair of glasses, which can solve the problem of “myopia and presbyopia”. The optical transition is smooth and there is no obvious discontinuity in the degree. However, the fitting requirements are high and the corresponding fitting parameters also require more precision. Among them, how to measure and select the progressive channel is a headache for many optical shops.In addition to domestic, sustainable sunglasses It has also emerged in the international field and gradually gained the favor of more foreign friends. https://ymoeyewear.com/
Nowadays, with the high penetration of the Internet, the middle-aged and elderly people have officially entered the era of small screens, and their eye health problems have been rapidly magnified. Adult progressive lenses can greatly meet the needs of presbyopic people to see both near and far with one pair of glasses.
However, progressive glasses have high requirements for fitting, and how to accurately and quickly measure the key fitting parameters – channel and ADD, has troubled many colleagues in optical shops. At this year’s Shanghai exhibition, a very practical tool was discovered that can quickly and accurately measure the progressive channel.
What is a progressive channel?
Simply put, the channel is the transition length of the progressive lens from far to near. Proper channel selection is one of the key factors in whether the progressive lens is comfortable and convenient to wear.
Note: The channel length of progressive lenses of different brands is different, so please ask clearly when ordering! Example: The channel length of Zeiss progressive lenses is the vertical distance from the fitting cross to the starting part of the near area.
When the distance diopter and ADD are determined, the longer the channel length, the smoother the change from near diopter to distance diopter. However, when selecting a long channel, the downward rotation ability of the eye should be considered. Insufficient downward rotation force can easily cause unclear near vision.
Tools Recommendation | Rapid Calculation of Progressive Channel
How to accurately measure the length of the progressive channel? Measure the position of the pupil on the support piece when using it for distance and near respectively, and then measure the vertical distance between the two.