CMOS cameras: state-of-the-art technology for neuronal functional imaging with high spatiotemporal resolution

Marco Canepari; Marco Canepari

doi:10.3934/biophy.2025024

AIMS Biophysics

2025, Volume 12, Issue 4: 499-509. doi: 10.3934/biophy.2025024

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Review

CMOS cameras: state-of-the-art technology for neuronal functional imaging with high spatiotemporal resolution

Marco Canepari ^{1,2
,
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1.
Univ. Grenoble Alpes, CNRS, LIPhy UMR5588, F-38000 Grenoble, France
2.
Institut National de la Santé et Recherche Médicale, Paris, France

Received: 01 September 2025 Revised: 03 October 2025 Accepted: 10 October 2025 Published: 14 October 2025

In the last decade, complementary metal-oxide semi-conductor (CMOS) cameras became the state-of-the-art technology in many biological applications, and the ability to reach high acquisition rates represents one of the characteristics that outperform previous technologies. In this review, I concentrated on neuronal functional imaging (voltage and/or ions) that requires recording fluorescence from multiples sites of a neuron or of a network at kHz rates to sample signals associated with neuronal excitability. After introducing the physical constrains of this type of imaging and reviewing the technologies used in the past, I analysed how CMOS can address the challenge of neuronal functional imaging. I focused on the characteristics of two CMOS cameras that are in use in my laboratory: DaVinci2K and Kinetix. DaVinci2K achieves high acquisitions rates at 14-bit depth by using parallel processing from 16 sub-sensors whereas Kinetix achieves higher spatiotemporal resolution by sampling fluorescence at 8-bit depth, but at the cost of decreasing the dynamic range which represents a limitation in several experimental scenarios. I present comparable membrane potential imaging recordings of action potentials from the axon initial segment, which were achieved at 20 kHz with the two cameras. Finally, I conclude the review with some perspective considerations on future availability of CMOS cameras that may overcome the performance of present devices and the limitations in developing optimal devices for biological and biomedical applications.
- CMOS,
- imaging,
- neuron,
- fluorescence,
- membrane potential
Citation: Marco Canepari. CMOS cameras: state-of-the-art technology for neuronal functional imaging with high spatiotemporal resolution[J]. AIMS Biophysics, 2025, 12(4): 499-509. doi: 10.3934/biophy.2025024

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Abstract

In the last decade, complementary metal-oxide semi-conductor (CMOS) cameras became the state-of-the-art technology in many biological applications, and the ability to reach high acquisition rates represents one of the characteristics that outperform previous technologies. In this review, I concentrated on neuronal functional imaging (voltage and/or ions) that requires recording fluorescence from multiples sites of a neuron or of a network at kHz rates to sample signals associated with neuronal excitability. After introducing the physical constrains of this type of imaging and reviewing the technologies used in the past, I analysed how CMOS can address the challenge of neuronal functional imaging. I focused on the characteristics of two CMOS cameras that are in use in my laboratory: DaVinci2K and Kinetix. DaVinci2K achieves high acquisitions rates at 14-bit depth by using parallel processing from 16 sub-sensors whereas Kinetix achieves higher spatiotemporal resolution by sampling fluorescence at 8-bit depth, but at the cost of decreasing the dynamic range which represents a limitation in several experimental scenarios. I present comparable membrane potential imaging recordings of action potentials from the axon initial segment, which were achieved at 20 kHz with the two cameras. Finally, I conclude the review with some perspective considerations on future availability of CMOS cameras that may overcome the performance of present devices and the limitations in developing optimal devices for biological and biomedical applications.

Acknowledgments

Data used in Figure 1 were produced by Fatima Abbas and supported by the Agence Nationale de la Recherche through two grants (ANR-21-CE18-0042 – Nav12RESCUE and Labex Ion Channels Science and Therapeutics: program number ANR-11-LABX-0015).

Conflict of interest

The author declares no conflict of interest.

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