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All Outputs (33)

Steering Mirror System with Closed-Loop Feedback for Free-Space Optical Communication Terminals (2024)
Journal Article
Graham, C., Bramall, D., Younus, O., Riaz, A., Binns, R., Scullion, E., …Bourgenot, C. (in press). Steering Mirror System with Closed-Loop Feedback for Free-Space Optical Communication Terminals. Aerospace, 11(5), Article 330. https://doi.org/10.3390/aerospace11050330

Precision beam pointing plays a critical role in free-space optical communications terminals in uplink, downlink and inter-satellite link scenarios. Among the various methods of beam steering, the use of fast steering mirrors (FSM) is widely adopted,... Read More about Steering Mirror System with Closed-Loop Feedback for Free-Space Optical Communication Terminals.

Topology Optimization of a Single-Point Diamond-Turning Fixture for a Deployable Primary Mirror Telescope (2024)
Journal Article
Bourgenot, C., Krumins, V., Bramall, D. G., & Haque, A. M. (2024). Topology Optimization of a Single-Point Diamond-Turning Fixture for a Deployable Primary Mirror Telescope. Aerospace, 11(1), Article 50. https://doi.org/10.3390/aerospace11010050

CubeSats, known for their compact size and cost effectiveness, have gained significant popularity. However, their limited size imposes restrictions on the optical aperture and, consequently, the Ground Resolution Distance in Earth Observation mission... Read More about Topology Optimization of a Single-Point Diamond-Turning Fixture for a Deployable Primary Mirror Telescope.

Integrated fiber optic spectrally resolved downwelling irradiance sensor for pushbroom spectrometers (2022)
Journal Article
Graham, C., Girkin, J. M., & Bourgenot, C. (2022). Integrated fiber optic spectrally resolved downwelling irradiance sensor for pushbroom spectrometers. Optics Express, 30(25), 45592-45598. https://doi.org/10.1364/oe.477699

We present an integrated fiber optic spectrally resolved downwelling irradiance sensor for pushbroom hyperspectral imagers. The system comprises of a cosine corrector and custom fiber patch cables, collecting the ambient light in a large solid angle... Read More about Integrated fiber optic spectrally resolved downwelling irradiance sensor for pushbroom spectrometers.

Spectral index selection method for remote moisture sensing under challenging illumination conditions (2022)
Journal Article
Graham, C., Girkin, J., & Bourgenot, C. (2022). Spectral index selection method for remote moisture sensing under challenging illumination conditions. Scientific Reports, 12(1), Article 14555. https://doi.org/10.1038/s41598-022-18801-9

Remote sensing using passive solar illumination in the Short-Wave Infrared spectrum is exposed to strong intensity variation in the spectral bands due to atmospheric changing conditions and spectral absorption. More robust spectral analysis methods,... Read More about Spectral index selection method for remote moisture sensing under challenging illumination conditions.

Freeform based hYperspectral imager for MOisture Sensing (FYMOS) (2021)
Journal Article
Graham, C., Girkin, J. M., & Bourgenot, C. (2021). Freeform based hYperspectral imager for MOisture Sensing (FYMOS). Optics Express, 29(11), 16007-16018. https://doi.org/10.1364/oe.425660

We present FYMOS, an all-aluminum, robust, light weight, freeform based, near infrared hYperspectral imager for MOisture Sensing. FYMOS was designed and built to remotely measure moisture content using spectral features from 0.7-1.7µm integrating an... Read More about Freeform based hYperspectral imager for MOisture Sensing (FYMOS).

Full-Field Terahertz Imaging at Kilohertz Frame Rates Using Atomic Vapor (2020)
Journal Article
Downes, L. A., MacKellar, A. R., Whiting, D. J., Bourgenot, C., Adams, C. S., & Weatherill, K. J. (2020). Full-Field Terahertz Imaging at Kilohertz Frame Rates Using Atomic Vapor. Physical Review X, 10(1), Article 011027. https://doi.org/10.1103/physrevx.10.011027

There is much interest in employing terahertz (THz) radiation across a range of imaging applications, but so far, technologies have struggled to achieve the necessary frame rates. Here, we demonstrate a THz imaging system based upon efficient THz-to-... Read More about Full-Field Terahertz Imaging at Kilohertz Frame Rates Using Atomic Vapor.

New opportunities of freeform gratings using diamond machining (2018)
Conference Proceeding
Bourgenot, C., Calcines, A., & Sharples, R. M. (2018). New opportunities of freeform gratings using diamond machining. In R. Navarro, & R. Geyl (Eds.), Proceedings Volume 10706, Advances in Optical and Mechanical Technologies for Telescopes and Instrumentation III. https://doi.org/10.1117/12.2312040

With the recent development of new ultra fine aluminium alloys and progress in the field of directly machined freeform surfaces, diamond machined freeform gratings could play an important part in future spectrographs or integral field units, particul... Read More about New opportunities of freeform gratings using diamond machining.

Design of freeform diffraction gratings: performance, limitations and potential applications (2018)
Conference Proceeding
Calcines, A., Bourgenot, C., & Sharples, R. M. (2018). Design of freeform diffraction gratings: performance, limitations and potential applications. In R. Navarro, & R. Geyl (Eds.), Proceedings Volume 10706, Advances in Optical and Mechanical Technologies for Telescopes and Instrumentation III. https://doi.org/10.1117/12.2312125

Spectroscopy is a key technique in astronomy and nowadays most major telescopes include at least one spectrograph in their instrument suite. The dispersive element is one of the most important components and it defines the pupil size, spectral resolu... Read More about Design of freeform diffraction gratings: performance, limitations and potential applications.

Development of Focusing Plasma Mirrors for Ultraintense Laser-Driven Particle and Radiation Sources (2018)
Journal Article
Wilson, R., King, M., Gray, R., Carroll, D., Dance, R., Butler, N., …McKenna, P. (2018). Development of Focusing Plasma Mirrors for Ultraintense Laser-Driven Particle and Radiation Sources. Quantum Beam Science, 2(1), Article 1. https://doi.org/10.3390/qubs2010001

Increasing the peak intensity to which high power laser pulses are focused can open up new regimes of laser-plasma interactions, resulting in the acceleration of ions to higher energies and more efficient generation of energetic photons. Low f-number... Read More about Development of Focusing Plasma Mirrors for Ultraintense Laser-Driven Particle and Radiation Sources.

Design, manufacture, and evaluation of prototype telescope windows for use in low-vision aids (2017)
Conference Proceeding
Young, L., Robertson, D., Love, G., Girkin, J., Cowie, E., Bourgenot, C., & Courtial, J. (2017). Design, manufacture, and evaluation of prototype telescope windows for use in low-vision aids. In A. J. Davis, C. F. Hahlweg, & J. R. Mulley (Eds.), Novel optical systems design and optimization XX. https://doi.org/10.1117/12.2272992

Pixellated Optics, a class of optical devices which preserve phase front continuity only over small sub areas of the device, allow for a range of uses that would not otherwise be possible. One potential use is as Low Vision Aids (LVAs), where they ar... Read More about Design, manufacture, and evaluation of prototype telescope windows for use in low-vision aids.

Diamond machining of a single shot ellipsoidal focusing plasma mirror (2016)
Conference Proceeding
Bourgenot, C., Crosby, D., & Robertson, D. (2016). Diamond machining of a single shot ellipsoidal focusing plasma mirror. In J. Kovacicinova (Ed.), Optics and Measurement International Conference 2016. https://doi.org/10.1117/12.2257414

Plasma mirrors have become an important tool in high power laser physics due to their ability to suppress laser pre-pulses and amplified spontaneous emission allowing a cleaner and sharper rising edge pulse to be focused onto a target. A PMMA ellipso... Read More about Diamond machining of a single shot ellipsoidal focusing plasma mirror.

Towards freeform curved blazed gratings using diamond machining (2016)
Conference Proceeding
Bourgenot, C., Robertson, D., Stelter, D., & Eikenberry, S. (2016). Towards freeform curved blazed gratings using diamond machining. In R. Navarro, & J. H. Burge (Eds.), Advances in optical and mechanical technologies for telescopes and instrumentation II. https://doi.org/10.1117/12.2231182

Concave blazed gratings greatly simplify the architecture of spectrographs by reducing the number of optical components. The production of these gratings using diamond-machining offers practically no limits in the design of the grating substrate shap... Read More about Towards freeform curved blazed gratings using diamond machining.

Resolution limits of pixellated optical components (2016)
Conference Proceeding
Cowie, E. N., Bourgenot, C., Robertson, D., & Courtial, J. (2016). Resolution limits of pixellated optical components. In A. J. Davis, C. F. Hahlweg, & J. R. Mulley (Eds.), Novel optical systems design and optimization XIX. https://doi.org/10.1117/12.2237826

Pixellated optical components, for example generalised confocal lenslet arrays (GCLAs), enable the design of optical devices which cannot be realised without introducing pixellation or a similar compromise. A key concern is the degradation of imaging... Read More about Resolution limits of pixellated optical components.

CHOUGH: implementation and performance of a high-order 4m AO demonstrator (2016)
Conference Proceeding
Bharmal, N. A., Basden, A. G., Bourgenot, C. J., Black, M., Dubbeldam, C. M., Henry, D. M., …Myers, R. M. (2016). CHOUGH: implementation and performance of a high-order 4m AO demonstrator. In E. Marchetti, L. M. Close, & J. Véran (Eds.), Adaptive Optics Systems V (990948-990948-7). https://doi.org/10.1117/12.2231721

CHOUGH is a small, fast project to provide an experimental on-sky high-order SCAO capability to the 4.2m WHT telescope. The basic goal has r0-sized sub- apertures with the aim of achieving high-Strehl ratios (> 0:5) in the visible (> 650 nm). It achi... Read More about CHOUGH: implementation and performance of a high-order 4m AO demonstrator.

Progress towards building pixelated transformation-optics devices (2015)
Conference Proceeding
Cowie, E., Bourgenot, C., Robertson, D. J., & Courtial, J. K. (2015). Progress towards building pixelated transformation-optics devices. In Frontiers in Optics 2015. https://doi.org/10.1364/fio.2015.fm3e.5

We report progress in the design and manufacture of micro-structured surfaces that change the direction of transmitted light rays. Such pixellated generalised refraction is general enough to design pixellated transformation-optics devices.

Realtime wavefront sensing in a SPIM microscope, and active aberration tracking (2015)
Conference Proceeding
Taylor, J. M., Saunter, C. D., Bourgenot, C., Girkin, J. M., & Love, G. D. (2015). Realtime wavefront sensing in a SPIM microscope, and active aberration tracking. In T. G. Bifano, J. Kubby, & S. Gigan (Eds.), . https://doi.org/10.1117/12.2080061

Adaptive optics (AO) can potentially allow high resolution imaging deep inside living tissue, mitigating against the loss of resolution due to aberrations caused by overlying tissue. Closed-loop AO correction is particularly attractive for moving tis... Read More about Realtime wavefront sensing in a SPIM microscope, and active aberration tracking.

AO modal optimization in a live, beating zebrafish heart (2013)
Conference Proceeding
Bourgenot, C., Taylor, J. M., Saunter, C. D., Girkin, J. M., & Love, G. D. (2013). AO modal optimization in a live, beating zebrafish heart. . https://doi.org/10.1364/aopt.2013.ow4a.4

We report on the combinated use of heart synchronization and wavefront sensorless modal AO to enable significant improvement in image quality of a live transgenic zebrafish embryo heart, imaged with a light sheet microscope.

Comparison of closed loop and sensorless adaptive optics in widefield optical microscopy (2013)
Journal Article
Bourgenot, C., Saunter, C., Love, G., & Girkin, J. (2013). Comparison of closed loop and sensorless adaptive optics in widefield optical microscopy. Journal of the European Optical Society-Rapid Publications, 8, Article 13027. https://doi.org/10.2971/jeos.2013.13027

We report on a closed loop widefield adaptive optics, optical microscopy system in which the feedback signal is provided by backscattered light from the sample acting as a guide star. The improvement in imaging performance is compared to an adaptive... Read More about Comparison of closed loop and sensorless adaptive optics in widefield optical microscopy.

Light sheet adaptive optics microscope for 3D live imaging (2013)
Conference Proceeding
Bourgenot, C., Taylor, J., Saunter, C., Girkin, J., & Love, G. (2013). Light sheet adaptive optics microscope for 3D live imaging. In C. J. Cogswell (Ed.), . https://doi.org/10.1117/12.2002057

We report on the incorporation of adaptive optics (AO) into the imaging arm of a selective plane illumination microscope (SPIM). SPIM has recently emerged as an important tool for life science research due to its ability to deliver high-speed, optica... Read More about Light sheet adaptive optics microscope for 3D live imaging.