Most
imaging systems are well described by a sequential list of surfaces;
each of which defines the boundary between one media and the next.
Rays are traced from the object surface to each surface in a specific,
sequential order.
 |
A
sample, sequential optical system. Light travels from one
surface to the next, to the next in a defined sequence |
Optical systems
such as camera lenses, telescopes, and microscopes are well
described by this model. Sequential ray tracing offers many
advantages for these systems, such as speed, flexibility, and
generality of surface shapes and properties. Sequential surface
based systems are also straightforward to optimize and tolerance.
Optical surfaces in ZEMAX may generally be reflective, refractive,
or diffractive. In addition, surface properties such as variable
transmission due to thin film coatings may be modeled in detail.
The bulk media between surfaces may be homogeneous, such as
common glass or air. Media may also be of an arbitrary gradient
index form; where the index is any complex function of position,
wavelength, temperature, or other properties. Birefringent materials,
where the index is a function of polarization state and ray
angle are also supported.
A great many surface and media types are predefined and ready
to use in ZEMAX. For special cases where an existing model is
not adequate, ZEMAX supports arbitrary user defined surfaces.
All properties of surfaces, including shape, refraction, reflection,
index, gradient index, thermal, polarisation, transmission,
and diffraction are user definable.
