We design and build microsystem solutions
NS THz Filters
At Nielson Scientific LLC, we aim to provide innovative solutions for the science and technology industry. Our Terahertz Filters will provide solutions to every section of a variety of industries.
Applications
Terahertz Filters
Results through Micro-Scale Ablation
At Nielson Scientific LLC, we have developed a rapid, low-cost manufacturing capability for THz filters based on our proprietary nano-ablation process. This approach allows us to eliminate slow and expensive photolithography-based fabrication steps and use lower-cost, high-performance starting materials.
Features
- Custom high-pass, low-pass, and bandpass filters ranges from 0.1THz to 10THz
- High transmittance 60%-90%
- Unwanted wavelengths are reflected rather than absorbed
- Extremely thin metal layers (100 nm to 1 µm)
- Fabricated on thin dielectric layers (typically 8µm polypropylene)
- Custom aperture sizes up to 600mm.
Performance
Nielson Scientific designs and manufactures passive filters for Terahertz and Far IR wavelengths. The metallic microstructures are designed with specific resistance, capacitance, and inductance which creates microscopic circuits which resonate with specific wavelengths, allowing those to transmit, but act as a mirror for unwanted wavelengths.
The plot to the left is an example of the bandpass performance you can expect.
More information
Filters can be placed in one of two categories: passive or active.
Passive filters include only passive components—resistors, capacitors, and inductors. In contrast, active filters use active components, such as op-amps, in addition to resistors and capacitors, but not inductors.
Passive filters are most responsive to a frequency range from roughly 100 Hz to 300 MHz. The limitation on the lower end results from the fact that the inductance or capacitance would have to be quite large at low frequencies. The upper-frequency limit is due to the effect of parasitic capacitances and inductances. Careful design practices can extend the use of passive circuits well into the gigahertz range.
Active filters are capable of dealing with very low frequencies (approaching 0 Hz), and they can provide voltage gain (passive filters cannot). Active filters can be used to design high-order filters without the use of inductors; this is important because inductors are problematic in the context of integrated-circuit manufacturing techniques. However, active filters are less suitable for very high-frequency applications because of amplifier bandwidth limitations. Radio-frequency circuits must often utilize passive filters.
https://www.allaboutcircuits.com/technical-articles/an-introduction-to-filters/