Image Sensor Power Supply Control for Weak-Light Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional solid-state image sensors face challenges in reducing power consumption while maintaining sensitivity, especially when detecting weak light, as lowering the power supply potential decreases sensitivity and brightness, particularly in low illuminance conditions.
Innovation Solution
The implementation of a solid-state image sensor with a photodiode, resistor, and power supply control unit that dynamically adjust the power supply potential based on measured illuminance, using a measuring unit to count potential drops and adjust power supply accordingly, allowing for lower power consumption without compromising sensitivity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If the power supply potential is decreased to reduce power consumption, then power consumption is reduced, but sensitivity of all pixels is decreased and brightness becomes insufficient in low illuminance conditions
Solution Approach 1:
The patent applies local quality by setting different power supply potentials for different pixel groups based on their respective illuminance conditions. Specifically, pixels are divided into first pixel groups (lower illuminance) and second pixel groups (higher illuminance), with the former receiving higher power supply potential to maintain sensitivity and the latter receiving lower power supply potential to reduce power consumption. This localized differentiation resolves the contradiction by tailoring power supply to actual needs of each region.
Solution Approach 2:
The patent implements dynamics by dynamically adjusting the power supply potential based on measured illuminance conditions. The illuminance measurement unit continuously monitors light levels, and the power supply control unit responds by switching between different power supply potentials. This dynamic adaptation allows the system to optimize the balance between power consumption and sensitivity in real-time according to actual operating conditions.
2Device complexity
If the power supply potential is controlled to the same value for all pixels, then circuit control is simplified, but power consumption cannot be reduced without affecting sensitivity
Solution Approach 1:
The patent applies segmentation by dividing pixels into multiple groups (first pixel groups and second pixel groups) with different power supply potentials. This segmentation allows independent power management for different regions, enabling power consumption reduction in high-illuminance areas while maintaining sensitivity in low-illuminance areas. The segmentation approach balances circuit control simplicity with power optimization by creating manageable groups rather than individual pixel control.
Solution Approach 2:
The patent implements parameter changes by varying the power supply potential parameter across different pixel groups based on illuminance conditions. Instead of using a fixed power supply potential for all pixels, the system changes the potential parameter dynamically - applying higher potentials to pixels needing sensitivity and lower potentials to pixels where power saving is prioritized. This parameter variation resolves the contradiction between simplified control and power consumption reduction.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach effectively reduces power consumption while maintaining sensitivity by adjusting power supply potential according to illuminance levels, optimizing energy use in both high and low light conditions.
Implementation Method 1
a photodiode configured to photoelectrically convert incident light and output a photocurrent
Data Source
AI summary
To reduce power consumption in a solid-state image sensor that detects weak light.The solid-state image sensor includes a photodiode, a resistor, a measuring unit, and a control unit. The photodiode photoelectrically converts incident light and outputs a photocurrent. The resistor drops a potential of one end of the photodiode to a value lower than a power supply potential every time a photocurrent is output. The measuring unit measures illuminance of the incident light on the basis of a frequency of dropping of the potential of one end. The control unit controls the power supply potential to a lower value as the measured illuminance is higher.