Interesser

• Solenergi
• Nonimaging optics
• Numerisk optimering

Tidsskriftartikler

• H. J. D. Johnsen, J. C. Miñano, and J. Torgersen, “Line-focus solar concentration 10 times higher than the 2D thermodynamic limit”, in Optics Express, 2022.
• H. J. D. Johnsen, A. Aksnes, and J. Torgersen, “Beyond the 2D limit: Étendue-squeezing line-focus solar concentrators”, in Optics Letters, 2020.
• H. J. D. Johnsen, A. Aksnes, and J. Torgersen, “High-performance stationary solar tracking through multi-objective optimization of beam-steering lens arrays”, in Optics Express, 2020.

Konferanseartikler

• V. Stubberud, A. Santamaría, H. J. D. Johnsen, “Designing freeform Fresnel lenses with continuous facets,” i Nonimaging Optics: Efficient Design for Illumination and Solar Concentration XIX, 2024.
• W. Cassarly, H. J. D. Johnsen, “Mixing rod with embedded mirrors,” i Nonimaging Optics: Efficient Design for Illumination and Solar Concentration XIX, 2024.
• V. Stubberud, M. Steinert, og H. J. D. Johnsen, “Democratising dry adhesion development with consumer-grade AM”, i Proceedings of the Design Society, 2024.
• H. J. D. Johnsen, J. Torgersen, “High-concentration freeform microtracking concentrators with single-axis external tracking,” i AIP Conference Proceedings 2841, 2023
• H. J. D. Johnsen, J. C. Miñano, “In search of a sharper line focus: Rotating the étendue,” i Nonimaging Optics: Efficient Design for Illumination and Solar Concentration XVIII, 2022.
• H. J. D. Johnsen, A. Aksnes, og J. Torgersen, “Pushing the limits of beam-steering lens arrays,” i Nonimaging Optics: Efficient Design for Illumination and Solar Concentration XVI, 2019.
• H. J. D. Johnsen, J. Torgersen, og A. Aksnes, “High-concentration wide-angle tracking integration with stacked lens arrays,” in 15th International Conference on Concentrator Photovoltaic Systems (CPV-15), 2019.
• H. J. D. Johnsen, J. Torgersen, og A. Aksnes, “Solar tracking using beam-steering lens arrays,” i Nonimaging Optics: Efficient Design for Illumination and Solar Concentration XV, 2018.

Undervisning

• TMM4150 Maskinkonstruksjon og mekatronikk (høsten 2024)
• TPK4125 Mekatronikk (våren 2024, våren 2023)
• MAST2001 Maskindeler 1 (høsten 2022)
• TMM4112 Maskindeler (deler av vårsemesteret 2022)

Priser

• “Young Scientist Award” på The 18th International Conference on Concentrator Photovoltaics (CPV-18), 2022.

Annet arbeid

• H. J. D. Johnsen, “A visual tour through the nonimaging optics literature,” SPIE Optics + Photonics 2024, 2024. (Presentasjon. Opptak)
• H. J. D. Johnsen, “Freeform beam-down secondary concentrators for heliostat fields,” SPIE Optics + Photonics 2024, 2024. (Presentasjon. Opptak)
• H. J. D. Johnsen, “Non-imaging Secondary Mirrors for Heliostat Fields,” Norwegian Electro-Optics Meeting, 23. mai 2024. (Presentasjon)
• H. J. D. Johnsen, J. C. Miñano, “Rethinking the Secondary Concentrator: A High-Concentration Retrofit for Linear Solar Collectors,” SolarPACES 2022, 2022. (Presentasjon)
• H. J. D. Johnsen, “The fascinating optics behind solar concentration,” TRANSNET Project Workshop. Zaragoza, Spain, 2022. (Invitert Presentasjon)
• H. J. D. Johnsen, “Improved line-focus solar concentration through étendue rotation,” Norwegian Electro-Optics Meeting, 2022. (Presentasjon)
• H. J. D. Johnsen, J. C. Miñano, “In search of a sharper line focus: Rotating the étendue,” SPIE Optics + Photonics 2022, 2022. (Presentasjon)
• H. J. D. Johnsen, and J. Torgersen, “High-Concentration Freeform Microtracking Concentrators with Single-Axis External Tracking,” The 18th International Conference on Concentrator Photovoltaics (CPV-18), 2022. (Presentasjon. Slides)
• H. J. D. Johnsen, J. C. Miñano, and J. Torgersen, “Towards a High-Concentration Line-Focus Concentrator: Étendue-Squeezing and Tracking Integration?,” SolarPACES 2021, 2021. (Poster. Opptak, PDF)
• H. J. D. Johnsen, “New approaches to solar tracking and concentration through numerical optimization of lens arrays,” PhD Disputaspresentasjon, 2020. (Presentasjon. Opptak)
• H. J. D. Johnsen, “Using the coldness of space: radiative cooling and power conversion,” PhD Disputas, Prøveforelesning, 2020. (Presentasjon. Opptak)
• H. J. D. Johnsen, A. Aksnes, og J. Torgersen, “Beam-steering lens arrays and ètendue-squeezing: a pathway towards a new class of solar concentrators?,” SPIE Optics + Photonics 2020, 2020. (Presentasjon. Opptak, Slides)
• H. J. D. Johnsen, A. Aksnes, og J. Torgersen, “Pushing the limits of beam-steering lens arrays,” SPIE Optics + Photonics 2019, 2019. (Presentasjon. Opptak, Slides)
• H. J. D. Johnsen, J. Torgersen, og A. Aksnes, “Design and fabrication of beam steering lens arrays through raytracing and maskless grayscale lithography,” 10th Annual Workshop of the Norwegian PhD Network on Nanotechnology for Microsystems, 2019. (Presentasjon)
• H. J. D. Johnsen, A. Aksnes, og J. Torgersen, “High-Concentration Wide-Angle Tracking Integration with Stacked Lens Arrays,” The 15th International Conference on Concentrator Photovoltaics (CPV-15), 2019. (Presentasjon. Slides)
• H. J. D. Johnsen, J. Torgersen, og A. Aksnes, “Tracking-Integrated Solar Energy Using Stacked Lens Arrays,” Norwegian Solar Cell Conference (NSCC) 2019, 2019. (Poster)
• H. J. D. Johnsen, J. Torgersen, og A. Aksnes, “Beam-steering lens arrays for solar tracking,” First NTNU Young Researcher Clean Energy Symposium, 2019. (Presentasjon)
• H. J. D. Johnsen, J. Torgersen, og A. Aksnes, “Beam-steering lens arrays for solar tracking,” NTNU Nano Symposium 2018, 2018. (Presentasjon)
• H. J. D. Johnsen, J. Torgersen, og A. Aksnes, “Solar tracking using beam-steering lens arrays,” SPIE Optics + Photonics 2018, 2018. (Presentasjon. Opptak)
• H. J. D. Johnsen, “Interview: Håkon J. Dugstad Johnsen – Beam steering lens array for solar cooking,” SunPod podcast, 2018. (Podcastintervju)
• H. J. D. Johnsen, J. Torgersen, og O. J. Nydal, “Beam Steering Lens Array for Solar Cooking,” The 10th International SolarZentrum Conference for food quality, solar cooking, drying, farming, and gardening, 2018. (Invitert Presentasjon)
• H. J. D. Johnsen, J. Torgersen, og O. J. Nydal, “Beam Steering Lens Array for Solar Cooking,” Consolfood 2018, 2018. (Presentasjon. Slides)