This article explains the operation of the MTF operands, and the choice of sampling schemes and algorithms available

Question: What does it mean to do a virtual propagation of rays?

This article explains:

• The meaning of F-Number for optical systems with non-circular stops
• The theoretical basis for the defined effective F-Number in Zemax

This article explains:

• What a ray is
• Rays and wavefronts
• Coordinates, cosines, and propagation
• Refraction, reflection, and diffraction 
• Amplitude. phase and optical path

This article is also available in Japanese.

 

This article explains:

• What paraxial rays are
• What parabasal rays are
• Differences between them that can cause confusion

The article is accompanied by a ZIP archive containing the samples used and a macro. This can be downloaded from the final page of the article.

This article is also available in Japanese.

This article explains:

• What is a Point Spread Function?
• The spot diagram
• The FFT PSF
• The Huygens PSF
• How to observe the Huygens integration using a Non-Sequential lens and detector
• How to choose between using the Huygens and FFT based PSF for a sequential lens

The article is accompanied by a ZIP archive containing the sample ZEMAX files used. This can be downloaded from the final page of the article.

This article is also available in Japanese.