What are Mirrors?
Mirrors and reflectors are designed to reflect broad wavelength ranges, or specific wavelength ranges in the case or hot mirrors and cold mirrors.
Omega Optical provides both turnkey mirrors coated on substrates we manufacture or source, or provide mirror coating services on customer supplied substrates.
Types of Mirrors
Enhanced Metal Mirrors
We produce Gold, Silver, and Aluminum mirrors with layers which enhance reflectivity and durability in the presence of abrasion and corrosive elements. These mirror coatings are often selected by our Defense, Railroad, and Environmental Monitoring customers.
First Surface Mirrors
A front or first surface mirror provides superior optical quality for engineering and scientific applications. Unlike a standard household mirror, which is coated on the second surface of the glass, a first surface mirror provide an accurate reflection without ghost images. Optical experts recommend first surface mirrors for use in precision optics applications.
Second Surface Mirrors
Second surface mirrors, similar to household mirrors, are useful in applications where the mirror surface must avoid direct contact. Ghost images can occur with second surface mirrors; please discuss with our Optical Experts whether a second surface mirror is right for your application
Off-axis Parabolic (OAP)
Omega Optical produces diamond turned off-axis parabolas in a variety of configurations, as well as coated or uncoated. We are specialists in producing OAP's with excellent mechanical or optical datums to ensure easy, precise, and repeatable alignment.
Spherical and Aspherical
We produce aspherical, off-axis, and other non-rotationally symmetric mirrors using computer controlled generation and diamond turning. Our coating techniques allow for uniform coatings on extremely fast convex and concave surfaces.
Questions About Mirrors
What should I consider when specifying a dielectric mirror?
The choice of dielectric mirrors depends on the following functional and operational specifications of your application:
- Wavelength characteristics: Do you need a mirror to combine different colors or split them? Do you need to select one wavelength band and/or reject another? Coming up with a desired reflection spectrum for the mirror is the first step towards finding a mirror best suited for your application.
- Mirror surface: Surface roughness is another criterion that needs to be considered. Does your application require a mirror with a flat, spherical or cylindrical surface?
- Reflectivity: Do you need 90% (household mirrors) or 99% (specialized industrial mirrors) or even 99.99% (laser mirrors) reflectivity? 90% reflectivity will not be enough for laser mirrors but it could work for a cold mirror used in HUDs. There will generally be a trade-off in terms of wavelength characteristics and reflectivity depending on the complexity of the application.
- Angle of Incidence (AOI): Again, this depends on the application and is a very important design criterion. A mirror designed to reflect 99.99% of light of a certain wavelength at 0o angle of incidence, will not achieve the same reflection at 45o. A HUD typically requires a 45o angle of incidence, whereas a linear laser cavity may require an angle of incidence of 0o.
- Operating environment: Where is the mirror being used? Inside a camera, a car or will it be mounted on a satellite? The operating environment will dictate the choice of substrate. The mirror needs to be designed to operate efficiently whether there is high humidity or high optical flux, or if it needs to be scratch resistant. These constraints will eventually determine the choice of the optical material.
- Tolerance: How precise do each of the above criteria need to be? This not only depends on the application but may also be influenced by practical aspects like balancing cost and performance. Size, thickness, spectral and angular tolerances need to be considered.