Glass optics are probably the kind of optics that are most familiar to people around the world and Nalux is an expert in making all kinds of glass optics. Glass is the material first known to have been used to make the simplest glass magnifying lenses that were the birth of the optics industry. While plastic optics are more suited to mass production consumer applications, glass optics are often required when high power or thermal stability are required or the optical system just won't work.
There are also many ways to fabricate glass optics and some of the more common ways are shown below.
Mask lithography and plasma etching.
This method of fabricating glass optics uses a material called a "photoresist" to cover parts of a material's surface and leave other parts uncovered. The material, often in the form of a 6" diameter by 1mm thick glass wafer, is then exposed to a reactive plasma that attacks the surface of the wafer etching away the unprotected regions while the photoresist protects the areas of the wafer that we don't want to etch. After etching, the photoresist is washed away and you end up with a glass wafer with micro structures etched into it's suface creating the glass optics.
Electron Beam Lithography and plasma etching.
This fabrication method for glass optics creates the photoresist covering on a glass wafer in a different way than does the Mask Lithography method but once the photoresist is in place the etching process to create the structures is the same resulting in glass optics of the size and shape desired.
Single Point Diamond Turning.
This method for fabricating glass optics basically uses a type of lathe (picture a lathe in a machine shop) to mechanically machine a surface to create a radially symmetrical optic. However, a single point diamond turning "lathe" can cost more than $1 million and can create structures smaller than one micron. Ideal for making lenses, this is one of the more common methods for making glass optics.
Diamond milling is a method used for fabricating glass optics that is similar to milling in a standard machine shop except these milling machines cut with a diamond bit and are capable of making structures smaller than one micron in size and can cost over $1 million dollars each.
Focused Ion Beam.
This method creates glass optics by ablating away a surface using a beam of ions. Very detailed and intricate structures can be made using this method. Unfortunately, it is slow so glass optics created this way can be very expensive.
This technique for creating glass optics is a proprietary technique that Nalux has developed. It is especially useful in molding large quantities of glass optics that are not symmetrical such as waveguides and multifunction optics such as a lens with a grating superimposed over the lens. Glass molding uses a charge of glass loaded into a mold cavity. The mold closes and under heat and pressure the glass flows to fill the mold cavity creating glass optics that have a wide range of optical function.
There are many different types of glasses used in making optics. Some types are only suitable for machining by diamond turning or other mechanical methods. Other types are best suited for the plasma etching process to make micro and nano structures. Still other glasses are best suited for a glass molding process. Some have higher melting temperatures, some have a higher refractive index, while others allow different wavelengths of light to pass or not to pass. So, just like metals and plastics, glasses cover a wide range of materials and the correct glass needs to be selected for the correct industrial or consumer application. Nalux stands ready to supply your glass optics needs now and in the future. Give us a call.
NALUX NANO OPTICAL, INC.
65 E.State Street, Suit2000
Columbus, Ohio 43215
c/o Schneider Downs
"Lighting a path to the future with nano-optics."