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When it comes to choosing a lens for your eyewear, it is important to consider the type of lens. There are two types of lenses you might want to consider: an aspherical or a spherical lens. There is a difference between the two, and you might like to know what that is. It is also interesting to compare the two types, thus discovering the importance of an aspherical lens vs. spherical lens.
An aspherical lens helps to reduce distortion, thus creating clearer vision. It eliminates optical imperfections such as curvature and chromatic distortion. The distortion is eliminated because the lens does not have any spherical shapes and is, therefore, flatter and thinner.
A spherical lens refers to the lens profile. This particular type of lens has a single curve that runs across the entire lens. These lenses are, therefore, also called singlets. The focal part of the lens is, therefore, dependent on the distance from the center area of the lens. This can lead to optical distortions. Figure 2 shows how the incoming rays in a spherical lens focus the different rays to a different point on the optical axis and, thus, the cause of distortion.
A spherical lens has a single curve that can make it bulkier and thicker than an aspheric lens. It can also, at some point, magnify the eyes, making it visually unappealing. It also adds weight to the overall eyeglass frame. With an aspherical lens, the lens can have varying curvatures. That is why the lenses can be flatter and thinner than spherical lenses.
Furthermore, the aspherical lens can be used in multi-focal or multi-vision eyeglasses because it can have varying curves. One could sum up the main differences between a spherical lens and an aspherical lens, that is, aspherical lens vs. spherical lens, as follows: the spherical lens is prone to distortion, and the aspherical lens can provide clearer or crisper vision.
Another difference is that aspherical lenses are more expensive than spherical lenses. The reason is that the manufacturing process requires more accuracy and precision. Aspherical lenses are, therefore, more difficult to make as opposed to the simpler spherical lenses.
Finding the right aspherical or spherical lenses is easy when you have online optical services. This service offers a wide range of eyeglasses that could help you decide on the right choice between an aspherical lens vs. spherical lens. The most important consideration here is to look at the difference in cost between the two options.
Included in the options is also the consideration of the size of the eyeglass frame. One might consider that the spherical lens, because of its nature, might require larger but lighter frames. You might opt for a frame such as Eirik that would allow for a wider vision.
Even so, you should check whether the glasses fit your face shape. The oval shape, of which Eirik is an example, is a universal shape. Another frame that you could opt for is the larger Minda frame. Both frames are lightweight and will allow any curvature. The lenses would definitely be less costly than the aspherical lenses.
Finding the right aspherical lens vs. spherical lens is much easier. In this instance, there is no need to be as careful in choosing a frame. However, once again, you should take the shape of your face into consideration.
The same applies to Azalea as below. In both of these examples, adding your aspherical lenses will not add any weight to your frame, even if you require multi-vision lenses. The only downside to aspherical lenses is that they are more costly than spherical lenses.
next day (PST)