Meet us at Photonics West 2025

We will be joining the and Photonics West 2025 exhibition from January 28th to January 30th.

Join us at SPIE Photonics West 2025, the world’s leading event for photonics, lasers, and optoelectronics. From January 28–30 at the Moscone Center in San Francisco, you’ll find us at booth 3321, showcasing our latest advancements in optical filters.

We specialize in the design and manufacturing of custom optical filters, including bandpass, edge, blocking, dichroic, and linear variable filters. Leveraging advanced design and deposition control software, we ensure a seamless transition from prototypes to volume production.

By maintaining an open dialogue with our customers about their requirements and the available technical possibilities, we consistently collaborate to deliver the best possible solutions

Explore Our Advanced Multi Bandpass Filters

Multi-bandpass filters are well suited for fluorescence spectroscopy instruments that need to work with multiple excitation wavelengths and/or multiple emission wavelengths.

We manufacture double, triple, and quad bandpass filters with high pass-band transmission and deep out-of-band blocking.

In combination with a range of LEDs, these filters are ideal for building fast and complex optical systems with no moving parts.

Read more about our Multi Bandpass filters here.

Revolutionizing Point-of-Care Diagnostics with Precision Fluorescence Filters

Experience the power of our fluorescence filters, designed specifically for point-of-care applications. These high-performance filters deliver unmatched precision, enabling rapid and reliable diagnostics when it matters most.

Discover how our cutting-edge technology is advancing healthcare by providing the accuracy and efficiency needed for critical diagnostic workflows.

Read more about our Point of Care filters here

Endless possibilities with Variable Filters

Continuously Variable Filters (CVFs) – also known as Linear Variable Filters – from Delta Optical Thin Film is wedged filters, whose spectral properties vary continuously along one dimension of the filter.

A single CVF for example can replace a large number of fixed filters or a grating based monochromator in an instrument. It is possible to adjust the center or edge wavelength by sliding the filter or rotating it.

CVFs are also ideally suited for order sorting in diode-array-based spectrometers.

Read more about our Variable Filters here

Setting the Standard in Fluorescence Filters

At Photonics West 2025, we’re spotlighting our industry-leading fluorescence filters, crafted for unparalleled performance in demanding applications. Designed with precision and innovation, these filters enhance fluorescence detection, delivering superior signal-to-noise ratios and optimal transmission.

Discover how Delta Optical Thin Film’s advanced solutions can elevate your fluorescence-based workflows, from cutting-edge research to clinical diagnostics. Let’s talk about how we can help meet your specific challenges – visit us to learn more!

Read more about our Fluorescense filters here

Meet our PW Team

Søren Helmer Rasmussen

Sales Director
DK, NO, SE, North America, Asian Pacific

Email: shr@deltaopticalthinfilm.com
Direct: +45 3154 1194

Oliver Pust

Sales Director
Europe (except DK, NO, SE), South America

Email: opu@deltaopticalthinfilm.com
Direct: +49 1575 6494917

We hope to see you at Photonics West


Meet us at W3+ Fair in Jena

We will be joining the W3+ Fair 25 + 26 September 2024 in Jena

Join us at the W3+ Fair Jena on September 25-26, 2024!

We’re excited to showcase our latest optical innovations, including our Order Sorting Filters, Variable Filters, and specialized Point of Care Filters.

This is a great opportunity to meet with our team, discuss your projects, and explore how our advanced solutions can meet your specific needs. Whether you’re looking for precision, flexibility, or cutting-edge technology, we have something to offer.

Don’t miss out—register now with code W2D851WR for free entry. We look forward to connecting with you at the fair!

Optical filters for Point of Care Applications

Did you know that we successfully help numerous Point of Care manufacturers with advanced optical filters?

Point of Care instruments based on fluorescence detection typically require high performance compact optical filters that can be manufactured cost-effectively in large quantities.

We specialize in all types of filters for fluorometers for Point of Care applications and use the latest magnetron sputtering technology. Filters can be diced to the smallest size. Hereby, we ensure a cost efficient, high-volume production of durable hard coated filters.

Read more about our filters for Point-of-Care.

Order sorting filters for fixed grating mini-spectrometers

Talk to our experts at our booth at W3+ to learn why our Continuously Variable Order Sorting Filters stand out as the preferred choice among prominent spectrometer suppliers.

There are many types of optical filters used for order sorting in grating-based spectrometers. However, continuously varibale filters are often the optimum choice due to the countinuosly varying filter edge and minimal edge artifacts.

Read more about our Order Sorting Filters.

Multi-Bandpass Filters for fluorescence microscopy

The combination of “any-color” LEDs and Multi-Bandpass Filters enables compact and very versatile fluorescence instruments to be built.

Such instruments can for instance be used to analyse complex reactions in real time involving multiple fluorophores.

Our Multi-bandpass Filters enable simultaneous transmission of multiple bandwidths with high precision and minimal cross-talk.

Read more about our Multi-Bandpass Filters.

Get your free ticket here


Meet us at Optatec 2024

We will be joining the Optatec 2024 exhibition 14 to 16 May 2024 in Frankfurt

As always we will demonstrate various types of our filters and we hope that you will visit us at booth 426 in hall 3.1, to have a talk about your application.

Optical filters for Point of Care Applications

Did you know that we successfully help numerous Point of Care manufacturers with advanced optical filters?

Point of Care instruments based on fluorescence detection typically require high performance compact optical filters that can be manufactures cost-effectively in large quantities.

We specialize in all types of filters for fluorometers for Point of Care applications and are using the latest magnetron sputtering technology. Filters can be diced to the small size. hereby, we ensure a cost efficient, high-volume production of durable hard coating filters.

Read more about our filters for Point-of-Care.

Order sorting filters for fixed grating mini-spectrometers

Talk to our experts at our booth at Optatatec to learn why our Continuously Variable Order Sorting Filters stand out as the preferred choice among prominent spectrometer suppliers.

There are many types of optical filters used for order sorting in grating-based spectrometers. However, continuously varibale filters are often the optimum choice due to the countinuosly varying filter edge and minimal edge artifacts.

Read more about our Order Sorting Filters.

Multi-Bandpass Filters for fluorescence microscopy

The combination of “any-color” LEDs and Multi-Bandpass Filters enable compact and very versatile fluorescence instruments to be built.

Such instruments can for instance be used to analyse complex reactions in real time involving multiple fluorophores.

Our Multi-bandpass Filters enable simultaneous transmission of multiple bandwidths with high precision and minimal cross-talk.

Read more about our Multi-Bandpass Filters.

We hope to see you on Optatec


New products: Quad-band emission filter and beamsplitter

Delta Optical Thin Film now offers filters with up to four wavelength pass-bands for multi-spectral fluorescence instrumentation.

The commercial availability of Light Emitting Diodes at almost any wavelength combined with Multi-Bandpass Filters have enabled a new type of Fluorescence instrumentation. These new instruments offer ultrafast switching between different wavelengths with-out the need for moving or replaceable filter parts.

We are proud to present our newest Multi-Bandpass filter products; a quad-band emission filter and a quad-band dichroic beamsplitter.

These products are excellent examples of the kind of filters that Delta Optical Thin Film can design and manufacture for our OEM-customers.

You can read more about our Multi-Band Filters and Dichroics below.


Meet us at Photonics West 2024

We will be joining the BIOS Expo and Photonics West 2024 exhibitions from January 27th to February 1st.

This is the largets photonics event in North America and it is a great opportunity to become updated on the latest trends in optical thin film filters

We are experts in optical thin film filters and have designed and manufactured those for more than 5 decades.

We constantly challenge the technology and develop new optical filters that efficiently solve advanced requirements in close dialogue with our OEM customers.

At the BiOS and Photonics West exhibitions in the Moscone Center in San Francisco you have the chance to discuss your optical filtering needs directly with our experts.

Make sure to swing by our booth:

BiOS: January 27 and 28th, Booth 8552

Photonics West: January 30th to February 1st, Booth 3552

We are dedicated to build strong OEM partnerships, believing that working together can lead to more efficient, cost-effective solutions. So, let’s have a talk about this.

Explore Our Advanced Multi Bandpass Filters

Multi-bandpass filters are well suited for fluorescence spectroscopy instruments that need to work with multiple excitation wavelengths and/or multiple emission wavelengths.

We manufacture double, triple, and quad bandpass filters with high pass-band transmission and deep out-of-band blocking.

In combination with a range of LEDs, these filters are ideal for building fast and complex optical systems with no moving parts.

Read more about our Multi Bandpass filters here.

The right Notch Filter for your needs

Notch Filters are designed to selectively block specific wavelengths while maintaining high transmission of other spectral regions.

Our notch filters are fully customisable in terms of centre wavelength and bandwidth, enabling applications in a broad range of practical technologies including Raman spectroscopy, fluorescence spectroscopy, microscopy and many other applications.

Contact us to initiate a discussion where we together can find the perfect solution for your precise optical filtering requirements.

Read more about our Notch Filters

Endless possibilities with Variable Filters

Continuously Variable Filters (CVFs) – also known as Linear Variable Filters – from Delta Optical Thin Film is wedged filters, whose spectral properties vary continuously along one dimension of the filter.

A single CVF for example can replace a large number of fixed filters or a grating based monochromator in an instrument. It is possible to adjust the center or edge wavelength by sliding the filter or rotating it.

CVFs are also ideally suited for order sorting in diode-array-based spectrometers.

Read more about our Variable Filters here

We hope to see you at Photonics West


Meet us at Laser World of Photonics 2023

We will be joining the Laser World of Photonics 2023 June 27th to 30th i Munich.

As always we will demonstrate various types of our filters and we hope that you will visit us at booth B1.142 to have a talk about your application.

Optical filters for Point of Care Applications

Did you know that we successfully help numerous Point of Care manufacturers with advanced optical filters?

The filters are manufactured on our new high capacity Helios 800 magnatron sputter coater and diced to smaller sizes. Filters are most often supplied in vacuum trays to prevent particles from conventional packing material.

Read more about our filters for Point-of-Care.

Come and tune your own filter

We will demonstrate our variable filters that can replace a series of homogenous filters in your application.

If you visit us at Laser World of Photonics you can try to tune your own filter.

See how you can get your application’s exact wavelength and bandwidth.

Read more about our continuously variable filters.

Let's meet in Munich

We warmly invite you to reach out to us now to schedule a meeting at Laser World of Photonics in Munich.

Our team is eagerly awaiting the opportunity to connect with you and discuss how our cutting-edge photonics solutions can meet your needs.

Don’t hesitate to contact us today, and let’s plan an engaging meeting that will propel us towards a brighter future in photonics.

We hope to see you on Photonics West


Meet us at Photonics West 2023

We will be joining the Photonics West 2023 exhibition from January 31st to February 2th.

As always we will demonstrate various types of our filters and we hope that you will visit us at booth 2426 to have a talk about your application.

Optical filters for Point of Care Applications

Did you know that we successfully help numerous Point of Care manufacturers with advanced optical filters?

The filters are manufactured on our new high capacity Helios 800 magnatron sputter coater and diced to smaller sizes. Filters are most often supplied in vacuum trays to prevent particles from conventional packing material.

Read more about our filters for Point-of-Care.

Come and tune your own filter

We will demonstrate our variable filters that can replace a series of homogenous filters in your application.

If you visit us at Photonics West you can try to tune your own filter.

See how you can get your application’s exact wavelength and bandwidth.

Read more about our continuously variable filters.

We hope to see you on Photonics West


We are rewarded with the "Potential 150"

Delta Optical Thin Film is rewarded with the ”Potential 150” award from Danske Bank. A reward dedicated to companies that inspires and makes a special difference.

As a justification for the award, Danske Bank emphasize our continues focus on sustainability which Danske Bank believed should act as a great source of inspiration for other companies.

Danske Bank put special attention on the construction process of our new headquarter where our focus on sustainability meant choosing a lot of “green” solutions not being the cheapest.

In addition, they also emphasize the way our products improve the quality of life for people bringing advanced optics into their everyday lives. For example, in the field of medical diagnostics.

We are honored to receive this award.


Delta Optical Thin Film A/S is moving into new facilities

Following strong growth Delta Optical Thin Film A/S is moving into its new purpose-built facilities in DTU Science Park in Hørsholm, Denmark. A new, larger facility became necessary as Delta Optical Thin Film A/S had outgrown its previous residence both in terms of production and office space. At the same time, the new manufacturing building offers a much cleaner production environment.

Delta Optical Thin Film A/S is moving into the new premises and simultaneously expanding its production capacity with new magnetron sputtering coaters, a new improved clean room, a completely new automatic ultrasonic cleaning line, and new dicing equipment.  Together these investments will not only increase the production capacity but also create a cleaner production environment allowing for higher quality products.

The new building is custom designed to accommodate the very particular needs of manufacturing high-performance optical filters. The two-storey building will allow further considerable growth. Its roof is fully covered with solar panels that will make a sustainable contribution to our energy consumption. Our new automated ultrasonic cleaning line is completely alcohol-free and allows for the best possible cleaning result without discharging any harmful wastewater. It adheres to Danish environmental protection laws that are among the strictest worldwide.

Since Delta Optical Thin Film A/S was incorporated in December 2014, the company has experienced a doubling of its revenue. This was achieved by expansion of its customer base, expansion into new territories and new applications such as hyperspectral imaging or laser scanning microscopy. This growth was enabled by investments into new coating machines and technologies.

About Delta Optical Thin Film

Delta Optical Thin Film is the leading supplier of advanced, high-performance continuously variable filters commonly used in a variety of biomedical imaging applications including laser scanning microscopy, hyperspectral imaging, compact spectrometers, fluorescence microscopy, monochromators, and micro-plate readers among others.

Delta Optical Thin Film also provides single, multiband, laser-line and broadband band pass filters, long pass filters, short pass filters, dichroic and polarizing beam splitters along with other custom coated optical components. All filters can be delivered in different shapes and sizes down to tiny filters for Point-of-Care (PoC) instruments, fully tested – both spectrally and visually – with dedicated equipment.

Delta Optical Thin Film offers a wide range of high efficiency durable hard coated filters that have set the standard for high performance and precise operation. With its unique design tools and decades of experience, Delta can provide highly competitive standard filters and customised filters and optical components to exacting customer specific applications.

We look forward to seeing you at our new address Fremtidsvej 1, 2970 Hørsholm, Denmark or at one of the next events!


OSA Industry Member Profile - Delta Optical Thin Film

By Samantha Hornback, Research & Program Development Coordinator, The Optical Society

OSA Industry Development Associates (OIDA) member Delta Optical Thin Film, Denmark, is the leading continuously variable filter manufacturer in the industry. Calling themselves “The Optical Filter Company,” Delta puts an emphasis on customization and the highest quality products. To learn more about Delta and what it’s up to now, OSA spoke with CEO Poul Svensgaard, CTO Henrik Fabricius and Director of Sales and Marketing Oliver Pust. What follows is an edited version of that conversation.

Tell me about your company and its primary market.

Delta Optical Thin Film develops and manufactures high quality components in high volumes for instrument builders like microscope vendors, manufacturers of microplate readers and other types of optical instrumentation that use optical interference filters, dichroics and beamsplitters. This is the founding idea of the company. Over the years, we have developed technology that allows us to control all aspects of design and manufacture of our components, while keeping prices low. Our history goes back to the 1970s, when the focus was mostly on interference filters for fluorescence microscopes. Today, we have a new focus on continuously variable filters in addition to the homogeneous ones we were founded upon.

Quite often, our clients are very skilled optical engineers, but they may not be aware of all the facets of integrating optical filters into an optical measurement chain. We can often assist and add value by simplifying an optical system. Clients requesting a very advanced optical filter sometimes submit drawings that are far too complicated. We can take that and make it feasible. Working very closely with clients’ development engineering teams is definitely a key to our success.

We are able to offer so much customization due to our own design and optical monitoring software (OMS). Not only can we design the filters, but we can also design and manufacture the tools needed to make those filters. This technology also enables us to make continuously variable filters, something commercially available coating machines simply cannot do. The area of proprietary software has been leading the way as an enabling technology for creating advanced filters at competitive prices.

What goals drive Delta?

We are very much focused on bringing benefit to the people of the globe and trying to make products that have an impact on people’s daily lives. Our goal is to sustain our business and continue its growth. It’s critical for us to stay competitive, to make sure that we are still a viable supplier and that we are able to drive innovation for our clients.

We work frequently in medical diagnostics, new medicines, drug discovery, food quality and, more recently, point-of-care instruments. We deliver small, inexpensive minifilters for point-of-care instruments, some of which can be used at home. Of course, in the current situation, there is growing interest and need for point-of-care instruments, particularly those that can deliver the results quickly. The interesting thing is that these kinds of applications are just as advanced as the big lab equipment used today. Automation drives the cost reduction for these complex, yet small, components.

Beyond these types of applications, we have been expanding into the semiconductor industry, hyperspectral imaging and many others. Recently, we even received a request from NASA.

One other aspect that we find incredibly important is sustainability, not only for our employees, but for our customers as well. As a Danish company, we are already very fortunate that more than 50% of the country’s energy comes from wind turbines. At Delta, our new facility’s whole roof will be covered by solar panels, and we continually work toward being completely green. We don’t use any substances that cannot be directly poured into the sewer except for the oil for our vacuum pumps, and the water we use to clean our glasses before coating can be completely discharged without further cleaning. We as individuals strive to live sustainably, and we look after our employees and customers equally.

Where do you expect the company to be in 10 years?

We can tell you that we have been growing and almost doubling our profits in the last five years, and we expect similar growth to continue, especially within the medical market. From our own internal point of view, we are currently building a new facility that the whole company will move into this August. Based on trends in the industry, our new building will have greatly updated clean-room facilities, and we have expanded our capacity by acquiring new coating technology and sputtering machines. This will be a completely customized building, and the opportunities are very exciting.

We’ve talked a lot about how you work with your customers to make exactly what they need. How does your relationship with the customers influence your business?

We are a company that focuses on specific customers—original equipment manufacturers (OEMs). We are not a catalogue company where we have a plethora of filters that a customer can choose from. The relationship is best if we can get a deep insight into what our customers really need, not necessarily what they say or write down as specifications of what they want to have. It’s really a dialogue with the customer from the start.

What is the best decision that Delta has made?

We all agree that the best decision Delta has made was to become our own company. This happened five and a half years ago, and it was the right thing for us. Previously, the company was held by a public research institute that was a self-owned entity, almost like a foundation. That was acceptable initially for moving the technology out of the university level, but converting to a 100% commercial company has been critical to our success. This, coupled with Henrik’s development of  high-performance continuously variable filters, created the foundation of our success.

Describe your career paths. What brought you all to where you are today?

Henrik and Poul both studied at the Technical University of Denmark. After completing his degree as M.Sc., Henrik went on earning a diploma as industrial researcher from the Academy of Technical Sciences and he worked on a number of different national research projects within optics. This made him receive the annual award of the Danish Optical Society in 1995 for his research in and realization of quasi inhomogeneous optical filters. His research and development of new optical coating techniques and technology for more than 30 years makes him a key stakeholder and enabler. Poul brings to Delta a more commercial focus. His career has mainly been with Danish companies, previously in acoustics and electronics. He joined Delta in 2008 and has focused on improving the customer experience and new technology. Oliver has a strong technical background as well. Before Delta, Oliver obtained a Ph.D. in laser optical measurement technology and worked in sales and product marketing. The opportunity to explore filters presented itself, and he made the switch.

Why did you decide to join OIDA, and what do you see as the value of that membership?

As a long-time individual member of OSA, Henrik advised the company that an OIDA membership would prove beneficial. We find that OIDA is an excellent platform with a good combination of all the scientific background but with an industrial reach that enables us to identify potential users of our technology. The recent webinars have been particularly valuable in times like these. Further, the workshops, market reports and the growing global outreach have helped our business greatly.