What types of wearable loupes are available on the market?

There are three systems of loupes:

Class I :single lens loupes,

Class II:Galilean loupes

Class III:kepler (prismatic)   loupes.

The single lens loupes are not suitable for professional use as magnification is too weak and the working distance too small, making ergonomic work posture impossible.

Galilean loupes offer a very light design, high depth of field and allow maximum magnification of approx. 4x.

Prismatic  magnifying systems can offer a higher level of magnification (up to approx. 8x); however they severely restrict the field of view, reduce depth of field and are by far heavier than Galilean loupes

Class I    


Single lens loupes (flat plane). Refractive power is measured in diopters.

Class II


Between 2.0 & 3.5 power magnification. These loupes are usually a Galilean design.
(from the 17th-century astronomer, Galileo Galilei).

Class III*


Between 4.0 & 8.0  power magnification

Class IV
Between 4.0 & 8.0 power magnification. Both of these classes are usually known as prismatic loupes and are a Keplerian design (from the 17th-century astronomer, Johannes Kepler).