Patented Precision Patterning of Multiple Dichroic Coatings, Balzers, EIS Optics, Oerlikon Optics, Unaxis

PixelTec™ innovative patterned optical coating technology, pioneered by Ocean Thin Films, is ushering in a new generation of optical filter capabilities. Traditional patterning processes such as metal masking or dicing & re-assembly have significant drawbacks that are overcome by the use of PixelTec.

PixelTec Optical Coatings with Microlithographic Precision
Ocean Thin Films pioneered the PixelTec patterned optical coating that combines modern optical thin film deposition techniques with microlithographic procedures. This patented process enables micron-scale precision patterning of multiple optical thin film dichroic coatings on a single substrate.

The PixelTec process is used to create multi-patterned arrays of different optical filters for use in multispectral sensors, dense wavelength division multiplexers, micro-electro-mechanical devices (commonly referred to as MEMS) and optical waveguide-based devices. PixelTec patterning can also be applied to multi-part bonded filter applications common to the manufacture of digital data projectors and CCD camera detectors. In fact, a wide variety of optical coatings can be patterned, including dielectric multi-layer reflectors, bandpass filters, dichroic edge filters and broadband anti-reflection coatings. In addition the innovative PixelTec process is used to deposit enhanced metal reflectors, low-reflectivity opaque metals and electrically conductive transparent patterns.

The PixelTec Process
The production of a patterned optical multi-layer coated element begins with the application of photoresist to the surface. To generate a pattern, we align the mask and then expose and develop the photoresist. This creates a resist pattern on the coating surface. Next, the prepared substrates are placed into a vacuum chamber for controlled deposition of the multi-layer coating.

After deposition of the filter, the patterned coating is rinsed in solvent, which removes any unwanted multi-layer and resist leaving the desired patterned filter coating. This sequence can be repeated as needed, allowing multiple filters to be deposited.


Patterned dichroic filter coatings have optical and physical properties comparable to Ocean Thin Films, high-specification, non-patterned coatings, and have very high resistance to humidity and temperature. And because the coatings are applied directly to substrates and devices, their mechanical resistance to shock and vibration is an improvement over commonly used bonded discrete filter windows.

Implications for Design Engineers
Photonics technologies are becoming smaller and more commonly integrated into microelectronic and micromechanical systems. With PixelTec patterned optical filters and components, engineers can integrate wavelength-selective filtering structures much earlier into the design process. What's more, because the deposition process delivers multi-layer optical structures directly onto a component, it is no longer necessary to make a physical transition from micron-sized, on-chip structures to macroscopic diced and bonded optical filter elements -- and back again -- for wavelength-selective integrated opto-electronic and opto-mechanical devices.

PixelTec optical coatings are increasingly used for purpose-specific performance in a multitude of medical, defense, and industrial applications - leading to more compact, robust, and cost-effective optical devices. For example, optical bandpass filters can be deposited directly onto waveguide structures or active photodetector regions, to create microscopic wavelength-selective detectors.

Multi-layer RGB color filters can be produced as a single filter array for devices such as CCD camera detectors and LCD display panels, or as a rotating filter wheel for projection display applications. Selected bandpass filters can be combined in arrays for use with multi-spectral detector systems, or patterned in a ring structure in industrial and medical fiber optic instruments. Also, patterned bandpass filters can be used in dense wavelength division multiplexer and photonics-based microprocessor applications. Optical filter coatings can be deposited onto MEMS structures to form "tunable" filter elements, waveguide relays, and switches (from deposited reflector and beamsplitter coatings) on micromechanical mounts.

PixelTec innovated patterned optical coating technology provides a precise, cost-effective means to integrate a variety of optical thin film coatings into the design and manufacture of an entire new generation of opto-mechanical and opto-electronic devices.