Photodiode Array Pixel Disabling for Dark Count Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing LIDAR systems face challenges with defective pixels in photodiode arrays, leading to issues such as high dark count rates and reduced sensitivity due to the need for managing defective pixels, which affects resolution and efficiency.
Innovation Solution
A photodiode array design that includes a column and row controller system to manage defective pixels by selectively enabling and disabling rows and columns, reducing the impact of high dark count rates and allowing for higher resolution and dynamic range control.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If photodiode arrays are used in LIDAR systems, then detection capability is improved, but defective pixels cause high dark count rates and reduced sensitivity
Solution Approach 1:
The patent extracts and removes defective pixels from the active photodiode array by identifying them through testing and disabling them via control circuits. This separates the harmful defective pixels from the functional array, eliminating their negative impact on dark count rates while preserving the detection capability of good pixels.
Solution Approach 2:
The patent changes the operational state of photodiode pixels by dynamically enabling or disabling individual pixels based on their performance characteristics. By altering the bias voltage or operational mode of defective pixels, the system prevents them from contributing to dark count noise while maintaining optimal operation of functional pixels.
2Reliability
If defective pixels are managed by disabling rows and columns, then sensitivity is improved, but device complexity increases due to controller systems
Solution Approach 1:
The patent segments the photodiode array into independently controllable rows and columns, allowing selective disabling of specific pixels through row-column intersection control. This segmentation enables precise management of defective pixels without requiring individual control of each pixel, reducing overall system complexity while maintaining sensitivity.
Solution Approach 2:
The control circuits serve multiple functions: they activate photodiodes during normal operation, disable defective pixels to reduce noise, and can potentially reconfigure the array for different detection modes. This multi-functionality reduces the need for separate dedicated circuits for each function, thereby managing complexity.
3Measurement precision
If all pixels in photodiode arrays are activated, then resolution is improved, but power consumption increases due to defective pixels
Solution Approach 1:
Instead of activating all pixels in the array, the patent applies partial action by selectively enabling only the functional pixels while disabling defective ones. This approach maintains the necessary resolution for accurate detection while consuming less power by keeping problematic pixels in a low-power or disabled state.
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
The solution enables a high-resolution photodiode array with improved sensitivity and reduced power consumption by effectively managing defective pixels, enhancing the performance of LIDAR systems.
Implementation Method 1
An array of pixels, each having a photodiode
Data Source
Figure 1
Figure 2
Figure 3a
AI summary
A sensor has plurality of pixels arranged in a plurality of rows and columns with row control circuitry for controlling which one of said rows is activated and column control circuitry for controlling which of said pixels in said activated row is to be activated. The column circuitry has memory configured to store information indication which of the pixels are defective, wherein each of the pixels has a photodiode and a plurality of transistors which control the activation of the photodiode. A first transistor is configured to be controlled by a column enable signal while a second transistor is configured to be controlled by a row select signal.