This New updated Phorpter has wide measureing range, its range of standard cylinder lens can reach up to 6D with the revolution 0.25D. In the range of 20, accuracy will be lower than 0.5, using the rotary prism with trimming gear.
And P. D. Can be adjusted from 48mm to 75mm, quick switch between near P. D, between near visual angle and far visual angle.
Features:
Synchronal cross cylinder: Rotating of the cross cylinder is synchronal with the adjustment of the cylinder axis.
Convenient operation, clear scale: With the special design, you can switch to the appropriate lens quickly.
Multifunctional auxiliary lens: This multifunctional auxiliary lens includes: Red-Green lens, polarizer, prism, stenopeic lens, etc.
Fast and accurate conclusion: There are two spherical lens turntables with 0.25D and 3D diopter steps.
Measuring range: +16.75D~0~-19D. You can adjust it much more accurately if you use the 0.12 auxiliary lens.
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