# Bioinspired phototransistor with tunable sensitivity for low-contrast target detection

## TL;DR

A new phototransistor inspired by human vision can detect low-contrast targets more accurately and resist noise better than traditional devices.

## Contribution

A bioinspired phototransistor with tunable sensitivity for low-contrast target detection and noise suppression is introduced.

## Key findings

- The device achieves a 1000-fold improvement in sensitivity for low-contrast signal detection.
- It exhibits significantly enhanced noise immunity compared to conventional photodetectors.
- The system performs exceptionally in detecting low-contrast targets in complex environments.

## Abstract

Accurate recognition of low-contrast targets in complex visual environments is essential for advanced intelligent machine vision systems. Conventional photodetectors often suffer from a weak photoresponse and a linear dependence of photocurrent on light intensity, which restricts their ability to capture low-contrast features and makes them susceptible to noise. Inspired by the adaptive mechanisms of the human visual system, we present a molybdenum disulfide (MoS2) phototransistor with tunable sensitivity, in which the gate stack incorporates a heterostructure diode—composed of O-plasma-treated MoS2 and pristine MoS2—that serves as the photosensitive layer. This configuration enables light-intensity-dependent modulation of the diode’s conductance, which dynamically in turn alters the voltage distribution across the gate dielectric and transistor channel, leading to a significant photoresponse. By modulating the gate voltage, the light response range can be finely tuned, maintaining high sensitivity to low-contrast targets while suppressing noise interference. Compared to conventional photodetectors, the proposed device achieves a 1000-fold improvement in sensitivity for low-contrast signal detection and exhibits significantly enhanced noise immunity. The intelligent machine vision system built on this device demonstrates exceptional performance in detecting low-contrast targets, underscoring its promise for next-generation machine vision applications.

Inspired by human vision, a MoS2 phototransistor with gate-tunable sensitivity enables precise detection of low-contrast targets and strong noise suppression for next-generation intelligent machine vision systems.