From Life Sciences to Industry:
Advancements in Optical Filters
Emerging applications and technology trends in optics

Emerging applications and technology trends in optics

Abstract:
Optical filters are essential components in a wide range of applications,from life sciences and industrial inspection to environmental monitoring andconsumer electronics.
Chroma Technology, a leading manufacturer in this field, has more than 30 years of expertise in creating awide range of both standard and highly customized optical filters. This white paper explores the technicaladvancements and capabilities of Chroma Technology’s filters, highlighting their applications and the company’s
approach to custom solutions.

Introduction to Optical Filters
Optical filters are indispensable components ina wide range of modern optical technologies,
playing a crucial role in various scientific, medical,
consumer and industrial applications. These
devices are designed to selectively transmit,
reflect, or block specific wavelengths of light,
enabling precise spectral control over. As
technology advances, the potential of opticalfilters continues to grow, particularly in someexciting new and emerging applications such asaugmented and virtual reality, advanced medical
imaging, environmental monitoring, and satellitecommunications.

Applications of Optical Filters inModern Technology
In the medical imaging industry, optical filters
are integral to techniques such as fluorescencemicroscopy and optical coherence tomography(OCT). These filters enhance the ability to
distinguish between different types of tissues andprovide detailed images of biological structures.

Environmental monitoring benefits from opticalfilters in devices that detect pollutants or analyze
atmospheric conditions. These filters allow
scientists to isolate specific wavelengths of light,
enabling the accurate identification of chemicalcompounds in the environment. This capability isessential for tracking climate change, monitoring
air quality, and managing natural resources.
In free-space laser optical communications,
optical filters are vital for data transmission fromground-air, air-air, and even over satellite networks.
The filters ensure that signals maintain spectral
integrity, reducing noise, enabling faster and morereliable communication. As the demand for highspeed internet and data services grows, the role of
optical filters in supporting these infrastructures
becomes increasingly significant.
Advancements in laser technology also highlightthe importance of optical filters, particularly inapplications involving ultrafast pulsed lasers.
These lasers, with pulses in the femtosecond topicosecond range, are used in precision machining,
medical procedures, and scientific research.

Chroma Technology Corp

Types of Optical Filters
Multiband Filters
Multiband filters from Chroma Technology aredesigned to transmit multiple wavelengths
simultaneously while blocking others. These filters
are crucial in applications requiring high-speedacquisitions, such as fluorescence microscopy,
machine vision, and semiconductor inspection.
Technical Specifications and Applications

Tunable Filters

Wavelength range: Multiband filters can have

Tunable filters from Chroma allow users toa number of distinct bands, with bands ranging
from the UV to SWIR all in the same filter - thepossibilities are almost limitless.
Numbers of bands and bandwidth variation:

dynamically adjust the transmission band byaltering the angle of incidence. These filters arevaluable in spectroscopy and multispectral imaging,where flexibility and precision are necessary.

Chroma Technology has routinely made filters withfour and five bands, and has also demonstrated

Technical Specifications and Applications

the ability to make multibands with seven distinct

Angle of incidence adjustment: Chroma’s tunablebands.

filters work by adjusting the angle of incidenceOD (optical density) performance: Capable ofwhich causes the passband to shift. A 10nm wide

achieving OD6 between passbands, ensuring

tunable bandpass filter, for example, could have aminimal crosstalk and high precision.

0deg AOI centre-wavelength at 630nm, and shift

Use Case
A life sciences application required a multiband
filter with 7 narrow bands from UV to VIS, plusa long-pass for NIR light) for sequential laser
excitation, where speed was paramount. Traditional
filter wheels were too slow for the millisecond
switching times needed. Chroma’s multiband filter
provided a static solution, enabling rapid sequential
acquisition without moving parts.

down to a centre-wavelength of 550nm at 60deg
AOI, all while maintaining the 10nm bandwidth, andproviding high transmission, and excellent nearband / out-of band blocking:Emerging applications and technology trends in optics

Use Case
In the display manufacturing industry, these filtershelp ensure that color reproduction on screens
meets the highest standards. The precise matchto CIE functions reduces noise and enhances thereliability of color measurements, contributing toconsistent quality across devices.

Wavelength range: Can cover UV to SWIR
wavelengths with a single set of filters.
Precision: Requires precise angle control for
accurate wavelength tuning.
Use Case
A customer developed a broadband lightsource and used Chroma’s tunable filters tooffer customisable wavelengths for different
applications. This setup allowed the customer
to cover a wide spectral range with fewer filters,
significantly reducing costs and complexity.

Tristimulus Filters
Chroma’s tristimulus filters are essential for
accurate color measurement in display technology.
These filters are designed to match the CIE color

Mid-wave Infrared (MWIR) Filters
Chroma’s entry into the SWIR and now MWIR
range expanded the company’s capabilities into
new domains, including remote sensing and gas
analysis. These filters offer superior transmission,
steeper slopes, and deeper blocking compared tomany competitors.
Technical Specifications and Applications

matching functions, which are critical for calibratingWavelength range: 3 to 6 microns.

and verifying color accuracy in consumer

Material adaptation: Use of silicon or sapphireelectronics.

substrates for better performance in MWIR.

Technical Specifications and Applications
Low f1 prime score: Achieves less than 1%
deviation from the CIE standard, ensuring highaccuracy.
Field of view considerations: Customisable tomatch specific cone angles in various systems.

High transmission and blocking: Enables more
precise gas detection and remote sensing
applications.
Use Case
For environmental monitoring, Chroma’s MWIR
filters provide a better distinction between similargases, such as CO and CO2. This precision isChroma Technology Corp

crucial for applications such as Earth observation

take you through the process of creating somethingfrom satellites, where accurate gas differentiation

custom that will work. Chroma is here to solve yourcan impact climate studies and pollution tracking.

light problems!

Technological Edge
Sputter coating process: This enables precise
deposition for highly accurate filter performance.
Broadband monitoring: Ensures consistent quality
across the manufacturing process.
Customer collaboration: Chroma’s approach
involves close collaboration with customers tounderstand their challenges and deliver solutions
that enhance their applications. This customercentric focus has led to innovations that set
Chroma apart in the optical filter industry.
Chroma Technology’s advancements in opticalfilter design and manufacturing underscore thecompany’s commitment to quality and innovation.
Whether it’s multiband, tunable, tristimulus, MWIR,or any other type of optical filter, Chroma canCustom Solutions
One of Chroma’s strengths lies in its ability toprovide custom solutions tailored to specificcustomer needs. The company leverages itsexpertise in thin-film coating and precisionengineering to develop filters that meet uniquerequirements, whether it’s for a specific wavelength,
angle of incidence, or application environment.
So, if you’re looking for something a bit different,or you aren’t sure what might best work for yourparticular application, the expert team at Chroma
is here to help. Simply get in touch and let the teamknow what you are looking to achieve, and if theexisting range of products don’t quite fit, they will

provide a solution to meet the rigorous and specificdemands of modern applications.
Get in touch with the team at Chroma today to get ahead start on your application without delay.

“If you want to find the secrets ofthe Universe, think in terms ofenergy, frequency and vibration.”— Nikola Tesla

Corporate Headquarters
Chroma Technology Corp
10 Imtec Lane
Bellows Falls, VT 05101 USToll Free: 800-824-7662
Phone: 802-428-2500
Fax: 802-428-2525
sales@chroma.com

Chroma Technology GmbH
Maximilianstrasse 33
D-82140 Olching, Germany
Phone: +49 8142 4219701
Fax: +49 8142 4219701
europe@chroma.com

Chroma Technology Japan
8F Yokohama Onoecho Building
4-57 Onoecho Naka-ku
Yokohama 231-0015 Japan
Phone: +81 (0) 45 285 1583
Fax: +81 (0) 45 285 1501
japan@chroma.com

Chroma China
Room 611, Building 23, Harmony Times SquareNo. 268, Wangdun Road, SIP, Suzhou City
Jiangsu Province, 215028 China
Phone: +86-0512-66051705
china@cn.chroma.com

July 2024