Jackson cross-cylinder

The Jackson cross-cylinder is a lens of fundamental importance in optometry with a key role in the
refraction routine.

Jackson Crossed-Cylinder is a combination of two cylinders of equal strength but of opposite signs placed with their axis at 90 degrees to each other and mounted in a handle.

Jackson Crossed-Cylinder (JCC) technique is also called the flip- cross technique.

Slide Source: 
Indra Prasad Sharma, Optometrist at JDW National Referral Hospital, Bhutan

Optics:

  •  A typical JCC lens is a spherocylindrical lens having a spherical power component combined with a cylinder power component of twice the power of the sphere, and of opposite sign. 
  • Eg: +0.50 DS combined with -1.00 DC. This results in a net power of +0.50 DC in one axis and -0.50 DC in the other axis(+-50 DC). 
  • +0.50/-1.00 @90 

















































Where can we get JCC in Nepal??