SPAD Selection Circuit for Versatile Signal Routing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing photoelectric conversion apparatuses with single-photon avalanche diodes (SPAD) lack versatility due to direct connection of photons to digital counters, limiting their application and efficiency.
Innovation Solution
A photoelectric conversion apparatus featuring a selection circuit that connects first and second avalanche diodes to processing circuits, allowing for flexible signal routing and processing, enabling various operation modes such as imaging, distance measurement, and global shutter operations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If photons are directly connected to corresponding digital counters, then the structure is simple, but the versatility is poor
Solution Approach 1:
The patent implements a selection circuit that enables each digital counter to receive signals from multiple SPAD regions. This allows the same counter to be used for different imaging modes (imaging, distance measurement, depth imaging) by selectively connecting different SPAD regions, thereby achieving multi-functionality without increasing the number of counters and improving application versatility.
Solution Approach 2:
The patent introduces a dynamic connection mechanism through the selection circuit, which can flexibly change the connection relationship between SPAD regions and digital counters based on different operation modes. This dynamic reconfigurability allows the system to adapt between imaging mode, distance measurement mode, and depth imaging mode, resolving the contradiction between simple fixed connection and versatile flexible connection.
2Adaptability or versatility
If multiple SPAD regions are connected to the same digital counter, then the versatility is improved, but the signal routing complexity increases
Solution Approach 1:
The patent introduces a selection circuit as an intermediary component between the SPAD regions and digital counters. This selection circuit simplifies the signal routing by providing a centralized control mechanism that manages which SPAD region connects to which counter based on the current operation mode, thereby achieving versatile signal routing without proportionally increasing overall system complexity.
3Use of energy by moving object
If signals from second avalanche diodes are blocked during readout of first avalanche diodes, then the power consumption is reduced, but the operational complexity increases
Solution Approach 1:
The patent implements periodic action by dividing the operation into distinct phases: in imaging mode, the first SPAD regions are active while second SPAD regions are inactive (blocked); in distance measurement mode, the roles are reversed. The selection circuit controls the timing and blocking of signals periodically based on the current mode, reducing power consumption by ensuring only necessary circuits are active at any given time while managing operational complexity through mode-based control.
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 apparatus achieves high versatility and improved performance by allowing flexible connection of light detection circuits to processing circuits, enhancing area efficiency and reducing power consumption in different operation modes.
Implementation Method 1
one or more first avalanche diodes... configured to detect incident light
Implementation Method 2
single-photon avalanche diode (SPAD) regions
Data Source
AI summary
A photoelectric conversion apparatus includes one or more first avalanche diodes, a first processing circuit configured to be connected to the first avalanche diode(s), one or more second avalanche diodes, and a second processing circuit configured to be connected to the second avalanche diode(s), wherein the first avalanche diode(s) is/are configured to be connected to the second processing circuit by a selection circuit.