With the exception of our surplus components, all of our thin film and optical coatings are custom designed and fabricated. We excel in providing coatings for the infrared (IR) spectral region. Upon request, we can provide metrology and thin film characterization services.
Rugate Technologies has fabricated custom astronomical bandpass filters for the Gemini 8M Telescope Project at Hilo, HI. A set consists of a set of two complementary bandpass filters in the near-infrared (NIR) spectral region that provide in-band transmission over 80%, out of band blocking above OD 4, and superior edge slopes of 1.2%. These filters operate at cryogenic temperature. Call for pricing.
Thermophotovoltaic technology (TPV) is becoming a reliable means of generating electricity. Spectral control is a key factor in obtaining high efficiency in closed TPV systems. Rugate Technologies has developed the designs and fabrication processes to deposit interference filters specifically for TPV. The short pass filter exhibits very high in-band transmission, a sharp edge slope, and high out-of-band reflection over a broad spectral range.
RTI offers a variety of metal films and coatings. Standard products include:
Standard sizes are available (any optical components catalog items).
Standard metal film materials are:
Custom mirrors and coatings are available. This includes alternate metals, substrates, and masking. We also offer wafer metalization services with rapid turn around for wafers from 1 to 8 inches in diameter.
Aluminum mirrors and variable density filters are available in standard and custom sizes on glass, plastic, and silicon wafers. The opacity or optical density of a film is a function of film thickness. Figure 1 presents film transmission and optical density as a function of film thickness. For films of sufficient thickness (greater than a few hundred angstroms), the reflection of recently deposited aluminum is essentially constant. Aluminum will oxidize over time and reflectivity will degrade. An overcoat of magnesium fluoride is available for protection of the aluminum film against oxidation. Figure 2 presents visible reflection in the visible for both freshly deposited aluminum and protected aluminum.
Mirrors, optical density filters, and variable density transmission filters are available on standard glass and plastic substrates. We also offer wafer aluminizing services.
Figure 1: The transmission through a thin aluminum film is a function of film thickness. We fabricate standard and custom filters with variable transmission and reflection. Applications include selective attenuation of laser sources or improved uniformity of light sources.
Figure 2: At sufficient thickness, the reflectivity of an aluminum mirror is essentially independent of further increases in film thickness, however, the mirror oxidizes over time. A protective overcoat can be added to extend the life of the mirror. Reflectivity of a protected aluminum film, relative to a freshly coated aluminum film, is plotted versus wavelength. A loss in visible reflectivity of about 3% can be expected.
In additional to traditional discrete-layer optical coatings, Rugate Technologies, Inc. specializes in Rugate coatings. Rugate coatings are optical interference films where the refractive index of the film continuously and periodically grades as a function of the film's optical thickness. Rugate filters were originally conceived as a means of providing narrow reflection notch filters. By varying the index profile sinusoidally, rather than as a square wave, and by controlling the index excursion, very narrow notch filters free of higher order harmonics can be produced. Due to the lack of higher order harmonics, multiple index profiles can be easily superimposed to produce complex spectral performance.
We offer spatially variable neutral density filters for precise light intensity control. These economical filters are manufactured by grading the thickness of a metal film so that the transmission and reflection are varied in a linear fashion. The optical density of the filters shown below vary from near 0 to 4.5 or greater across 3 mm. Call to specify your optical density requirements.
Above: Optical density measured across the film’s edge after dicing.
We offer rapid turn-around for wafer metallization and can handle a single one-time cassette of prototype wafers or we can work with you to set up a regular coating schedule. Wafer sizes from 1 to 8 inches can be accommodated.
Typical Aluminum Thickness: 7500 Angstroms
Cleaning: Per Customer Specification
Call for pricing on other materials (for example, Germanium or Chrome).
*A note on sales: RTI tries to avoid typographical errors and maintain updated information. However, pricing is subject to change at any time.
Please read our Terms and Conditions/Ordering Information for specifics on shipping and handling, pricing, payment, warranty, and other important information regarding your purchase.
SHIPPING: Unless otherwise directed, shipment will be by the method Rugate Technologies, Inc. deems appropriate, F.O.B. Rugate Technologies' offices. Shipping costs are prepaid and added to the customer's invoice.
PRICING: All prices are in U.S. dollars. Surplus optics are available in limited quantities and are subject to prior sale. Prices are subject to change without notice. Listed prices do not include taxes, duties, freight, or insurance charges. We are not responsible for typographical errors.
PAYMENT: Payment may be made by credit card, through PayPal or Billpoint or payment may be prepaid, COD, Net 10 for approved purchase orders.
WARRANTY: The buyer has the right to return the products to Rugate Technologies, within 30 days after receipt, for replacement or full credit.