The 67th JSAP Spring Meeting 2020

Presentation information

Oral presentation

3 Optics and Photonics » 3.4 Biomedical optics

[15p-B309-1~9] 3.4 Biomedical optics

Sun. Mar 15, 2020 1:15 PM - 4:00 PM B309 (2-309)

Izumi Nishidate(TUAT)

3:15 PM - 3:30 PM

[15p-B309-7] Brightness illusions using bacteriorhodopsin-based binary DOG filter

〇(M1)Kohei Funaki1, Katsuyuki Kasai2, Yoshiko Okada-Shudo1 (1.The Univ. of Electro-Commun., 2.NICT)

Keywords:bacteriorhodopsin, receptive field, retinal ganglion cells

Retinal ganglion cell's receptive fields have a coaxial-shaped structure formed by the central excitatory and outer inhibitory regions. These regions respond oppositely to light. This shape can be mathematically modeled by a balanced DOG function.
Bacteriorhodopsin (bR) is a photosensitive protein which resembles the visual pigment rhodopsin. BR generates a transient polarity reversal photocurrent only when the light switches on or off.
We fabricate a DOG filter based on bR, which mimics the ganglion cell receptive fields. This filter consists of bR dip-coated thin films and the electrolyte solution that are sandwiched between ITO electrodes. We coat center disk and concentric ring patterns with different thickness of bR films, which correspond to the excitatory and inhibitory regions, on the front and rear ITO plates.
We apply bR-DOG filter to low-level brightness–contrast illusions, Hermann grid, Grating induction and Mach band. These images have been scanned on the bR-DOG filter to verify the occurrence of the illusion similar to vision. BR-DOG filter is useful to constructively understand the visual information processing system.