Product / Technical

Q. What method are the lenses manufactured by?

A. Most of our products are manufactured by Heat compression molding. Please contact us for more details.

Q. What does “Aperture” of Fresnel lens mean in specification?

A.We carry two types of Fresnel lenses: one type in which the Fresnel grooves do not extend to the corners (which are flat), and one type in which the Fresnel grooves extend to the corners of the lens.

For example, the CF50-B has a size of 100mm square and an aperture of 100mm. In this case, the size and aperture are the same because the corners have flat areas.

In contrast, the CF150-B has a size of 200mm but an aperture of 283mm. This is because the grooves cover the full surface of the lens.

Q. What is the heat resistance of the lenses?

A. Most of NTKJ’s standard products are made of PMMA.   PMMA’s “Heat Deflection Temperature” is approximately 95 degrees Celsius.  Therefore we recommend to maintain under 80 degrees Celsius to have safety margin. For heat exposure lasting longer, it is recommended to operate lower than 60 degrees Celsius approximately.  We always recommend you to purchase sample lenses to tryout at your operating environment to verify and verify functionality.