Mr. Roland Künzel Profile

Roland Künzel

at Covestro AG

SPIE Involvement:

Author

Publications (5)

Proceedings Article | 4 March 2022 Presentation + Paper

Reliable photopolymer for new applications: vHOEs recorded into Bayfol HX film resisting the environment

Friedrich-Karl Bruder, Johannes Frank, Sven Hansen, Roland Künzel, Jonas Künzel, Alexander Lorenz, Christel Manecke, Richard Meisenheimer, Jack Mills, Lena Pitzer, Igor Pochorovski, Thomas Rölle

Proceedings Volume 12026, 1202602 (2022) https://doi.org/10.1117/12.2607740

KEYWORDS: Holograms, Glasses, Humidity, Holography, Heads up displays, Head-mounted displays, Reliability

Read Abstract +

Bayfol^® HX photopolymer films prove themselves as easy-to-process recording materials for volume holographic optical elements (vHOEs) and are available in customized grade at industrial scale. Their full-color (RGB) recording and replay capabilities are two of their major advantages. Moreover, the adjustable diffraction efficiency, tunable angular and spectral selectivity of vHOEs recorded into Bayfol^® HX as well as their unmatched optical clarity enables superior invisible “off Bragg” optical functionality. As a film product, the replication of vHOEs in Bayfol^® HX can be carried out in a highly cost-efficient and purely photonic roll-to-roll (R2R) process. Utilizing thermoplastic substrates, Bayfol^® HX was demonstrated to be compatible to state-of-the-art plastic processing techniques like thermoforming, film insert molding and casting, which opened using a variety of industry-proven integration technologies for vHOEs. Therefore, Bayfol^® HX makes its way in applications in the field of augmented reality such as Head-up-Displays (HUD) and Headmounted- Displays (HMD), in free-space combiners, in plastic optical waveguides, and in transparent screens. Also, vHOEs made from Bayfol^® HX are utilized in highly sophisticated spectrometers in astronomy as well as in narrow band notch filters for eyeglasses against laser strikes.

Especially in the automotive application field the required reliability performance is very high and demanding. Bayfol® HX film itself and its integration in respective parts were further optimized to show significantly increased resilience against environmental conditions. Those parts pass automotive standard tests like accelerating weathering tests (PV 3930) and thermal cycling test (PV 1200), while keeping the performance level of the vHOEs recorded into Bayfol^® HX film unchanged. This enables a long-term stability of the final product and thus enabling the material to be used in even more applications. This especially holds true for permanent or most frequently outdoor applications such as automotive lighting, HUD or HMD.

Proceedings Article | 1 April 2020 Presentation + Paper

New ways how to apply Bayfol HX® film into recording stacks and into optical parts

Friedrich-Karl Bruder, Johannes Frank, Sven Hansen, Roland Künzel, Christel Manecke, Richard Meisenheimer, Jack Mills, Lena Pitzer, Thomas Rölle, Brita Wewer

Proceedings Volume 11367, 1136715 (2020) https://doi.org/10.1117/12.2555429

KEYWORDS: Holograms, Chemistry, Holography, Coating, Adhesives, Optical components, Volume holography, Glasses, Interfaces

Read Abstract +

See-through optical components are being intensively studied in applications such as Head-up-displays (HUD) and Head-mounted-displays (HMD). In particular, volume holographic optical elements (vHOE) have received a lot of attention due to their unique optical (angular and spectral selectivity) and mechanical (lightweight and thin) characteristics which make them perfectly suitable for use in integrated optical components like spectacle lenses and car windshields. Bayfol® HX photopolymer films prove themselves as easy to process recording materials for vHOEs. The Bayfol® HX instantly developing holographic photopolymer film provides full color capability and adjustable diffraction efficiency as well as an unprecedented optical clarity when compared to classical volume holographic recording materials like silver halide emulsions (AgX) or dichromated gelatin (DCG). Besides the recording step, no pre- or postprocessing is necessary and easy mass production of vHOEs in a completely dry roll to roll process is possible. The layout of a typical Bayfol® HX film consists of a light-sensitive photopolymer layer coated onto a transparent substrate and protected on the other side by a cover film. The substrate is particularly beneficial, not only for easy handling of the film during holographic recording, but also for further mechanical processing steps which are required to embed the film into a finished optical component. However for certain applications it is desirable to remove the substrate before or after recording. This will allow the user to make full use of the high flexibility of the photopolymer layer, for example if it comes to curved surfaces that have to be covered. Also more complex stack geometries can be realized in which the photopolymer layer could be embedded in optically well designed cavities or mechanically demanding setups. To facilitate this, we developed Bayfol® HX film grades in which the substrate has a lower adhesion to the photopolymer layer compared to the protective cover film. Therefor the substrate can be removed first in contrast to existing Bayfol® HX film grades which only allow to remove the protective cover film. On the other hand the adhesion of the protective cover film can also be well controlled, so that it can be specifically selected according to the needs of the surface to which the photopolymer layer has to be transferred to. In this paper we demonstrate versatile application processes making use of these transfer grades of Bayfol® HX films with respect to adhesion design, integration in complex stacks and application on curved surfaces.

Proceedings Article | 21 February 2020 Presentation + Paper

Expanding possibilities how to apply Bayfol HX(R) film into recording stacks and optical parts

Friedrich-Karl Bruder, Johannes Frank, Sven Hansen, Roland Künzel, Christel Manecke, Richard Meisenheimer, Jack Mills, Lena Pitzer, Thomas Rölle, Brita Wewer

Proceedings Volume 11306, 113060C (2020) https://doi.org/10.1117/12.2546220

KEYWORDS: Holograms, Chemistry, Holography, Coating, Adhesives, Optical components, Volume holography, Glasses, Interfaces

Read Abstract +

The layout of a typical Bayfol® HX film consists of a light-sensitive photopolymer layer coated onto a transparent substrate and protected on the other side by a cover film. The substrate is particularly beneficial, not only for easy handling of the film during holographic recording, but also for further mechanical processing steps which are required to embed the film into a finished optical component. However for certain applications it is desirable to remove the substrate before or after recording. This will allow the user to make full use of the high flexibility of the photopolymer layer, for example if it comes to curved surfaces that have to be covered. Also more complex stack geometries can be realized in which the photopolymer layer could be embedded in optically well designed cavities or mechanically demanding setups. To facilitate this, we developed Bayfol® HX film grades in which the substrate has a lower adhesion to the photopolymer layer compared to the protective cover film. Therefor the substrate can be removed first in contrast to existing Bayfol® HX film grades which only allow to remove the protective cover film. On the other hand the adhesion of the protective cover film can also be well controlled, so that it can be specifically selected according to the needs of the surface to which the photopolymer layer has to be transferred to. In this paper we demonstrate versatile application processes making use of these transfer grades of Bayfol® HX films with respect to adhesion design, integration in complex stacks and application on curved surfaces.

Proceedings Article | 23 April 2019 Presentation + Paper

How to integrate volume holographic optical elements (vHOE) made with Bayfol HX film into plastic optical parts

Friedrich-Karl Bruder, Sven Hansen, Tim Kleinschmidt, Roland Künzel, Christel Manecke, Enrico Orselli, Christian Rewitz, Thomas Rölle

Proceedings Volume 11030, 110300C (2019) https://doi.org/10.1117/12.2521088

KEYWORDS: Holograms, Adhesives, Holography, Glasses, Volume holography, Mirrors, Holographic optical elements, Silicon, Integrated optics, Diffraction

Read Abstract +

See-through optical components are being intensively studied in applications such as Head-Up-Displays (HUD) and Head-Mounted-Displays (HMD). In particular, volume holographic optical elements (vHOE) have received a lot of attention due to their unique optical (angular and spectral selectivity) and mechanical (lightweight and thin) characteristics which make them perfectly suitable for use in integrated optical components like spectacle lenses and car windshields. Bayfol HX photopolymer films prove themselves as easy to process recording materials for vHOEs. The Bayfol HX instant developing holographic photopolymer film provides full color capability and adjustable diffraction efficiency as well as an unprecedented optical clarity when compared to classical volume holographic recording materials like silver halide emulsions (AgX) or dichromated gelatin (DCG). Besides the recording step, no pre- or postprocessing is necessary and easy mass production of vHOEs in a completely dry roll to roll process is possible. The layout of a typical Bayfol HX film consists of a light-sensitive photopolymer layer coated onto a transparent thermoplastic substrate. This substrate is particularly beneficial, not only for easy handling of the film during holographic recording, but also for further mechanical processing steps which are required to embed the film into a finished optical component. Once holograms have been recorded and the film has been bleached with incoherent light, the Bayfol HX film becomes inert and can be further processed in normal daylight. Moreover, the presence of a thermoplastic substrate makes the film attractive for use in manufacturing processes such as injection molding, thermoforming, casting, etc…, typically used to fabricate parts for the automotive, eyewear and ID-card industry. Being compatible with these industrial processes is an essential feature for the widespread of immersive Augmented Reality displays based on volume holographic optical elements recorded into Bayfol HX films. In this paper we investigated the compatibility of holograms made with Bayfol HX film with some of the integration processes typically used in the plastic and optical components industry and which are necessary for embedding the holographic films into a finished product.

Proceedings Article | 1 March 2019 Presentation + Paper

Integration of volume holographic optical elements (vHOE) made with Bayfol® HX into plastic optical parts

Friedrich-Karl Bruder, Sven Hansen, Tim Kleinschmidt, Roland Künzel, Christel Manecke, Enrico Orselli, Christian Rewitz, Thomas Rölle

Proceedings Volume 10944, 1094402 (2019) https://doi.org/10.1117/12.2510109

KEYWORDS: Holograms, Adhesives, Holography, Holographic optical elements, Glasses, Silicon, Integrated optics, Volume holography, Mirrors, Optical components

Read Abstract +

See-through optical components are being intensively studied in applications such as Head-Up-Displays (HUD) and Head-Mounted-Displays (HMD). In particular, volume holographic optical elements (vHOE) have received a lot of attention due to their unique optical (angular and spectral selectivity) and mechanical (lightweight and thin) characteristics which make them perfectly suitable for use in integrated optical components like spectacle lenses and car windshields. Bayfol® HX photopolymer films prove themselves as easy to process recording materials for vHOEs. The Bayfol® HX instant developing holographic photopolymer film provides full color capability and adjustable diffraction efficiency as well as an unprecedented optical clarity when compared to classical volume holographic recording materials like silver halide emulsions (AgX) or dichromated gelatin (DCG). Besides the recording step, no pre- or postprocessing is necessary and easy mass production of vHOEs in a completely dry roll to roll process is possible. The layout of a typical Bayfol® HX film consists of a light-sensitive photopolymer layer coated onto a transparent thermoplastic substrate. This substrate is particularly beneficial, not only for easy handling of the film during holographic recording, but also for further mechanical processing steps which are required to embed the film into a finished optical component. Once holograms have been recorded and the film has been bleached with incoherent light, the Bayfol® HX film becomes inert and can be further processed in normal daylight. Moreover, the presence of a thermoplastic substrate makes the film attractive for use in manufacturing processes such as injection molding, thermoforming, casting, etc…, typically used to fabricate parts for the automotive, eyewear and ID-card industry. Being compatible with these industrial processes is an essential feature for the widespread of immersive Augmented Reality displays based on volume holographic optical elements recorded into Bayfol® HX films. In this paper we investigated the compatibility of holograms made with Bayfol® HX film with some of the integration processes typically used in the plastic and optical components industry and which are necessary for embedding the holographic films into a finished product.

View contact details

UPDATE YOUR PROFILE

Is this your profile? Update it now.

Sign into your SPIE.org account

Don’t have a profile and want one?

Create an account on SPIE.org

Keywords/Phrases

Search In:

Publication Years