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Contact lenses used in laser
Lens type Field of 
view 		 Laser spot 
magnification		 Spot size magnification
(Spot size set at 200mm)		 Corneal image 
distance
Volk Quadraspheric 1300 1.92 400 19mm
Mainster wide field 1250 1.47 294 30mm
Volk transequator 120-1250 1.43 286 28mm
Volk area centralis 80-900 1.01 200 38mm
Goldmann 3 mirror 360 1.08 216 -7mm
Note:

1. The smaller the image magnification, the larger the size of the burn for example Volk quadraspheric gives 
    half the image magnification of Volk area centralis but produces a laser burn spot of twice the size.

2. The larger the burn spot size, the lower the power density. The power of the laser may need to increase.

3. The larger the burn spot size, the lower the number of burn needed to cover a specified area.
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