TOF Distance Sensor Stabilizing Electrode Potential
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current distance measurement systems using the time-of-flight (TOF) method face challenges in achieving high detection accuracy due to potential changes in the electrode potential of light-receiving elements during periods when detection is not performed, leading to decreased accuracy.
Innovation Solution
Incorporating a photosensor with a light-receiving element and transistors that suppress potential changes during non-detection periods, allowing for multiple light emission and reflection detection cycles to enhance accuracy, and utilizing overlapping photosensors to reduce noise and improve detection precision.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the light-receiving element continuously detects reflected light during both light emission periods and non-detection periods, then more measurement data can be collected, but the electrode potential changes during non-detection periods causing measurement accuracy to decrease
Solution Approach 1:
The detection period is segmented into light emission periods and non-detection periods. During light emission periods, the light-receiving element actively detects reflected light for distance measurement. During non-detection periods, detection is suspended and the electrode potential is stabilized by disconnecting or resetting the light-receiving element, preventing potential drift that would otherwise occur during continuous detection.
Solution Approach 2:
Before each light emission period, a preliminary action is performed to reset or stabilize the electrode potential of the light-receiving element. This ensures that the detection begins with a known, stable potential baseline, eliminating the accumulation of potential changes from previous detection cycles and maintaining measurement accuracy throughout operation.
2Measurement precision
If multiple light emission and detection cycles are performed to improve measurement accuracy, then detection precision increases, but the complexity of controlling detection timing and potential stabilization increases
Solution Approach 1:
The distance measurement system employs periodic light emission and detection cycles with regular intervals. Each cycle consists of a light emission phase followed by a detection phase, repeating multiple times to accumulate measurement data. This periodic structure simplifies control by establishing a predictable rhythm that automatically manages when detection occurs and when potential stabilization should be performed, reducing the complexity of timing control while improving accuracy through multiple measurements.
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 high-accuracy distance measurement by stabilizing electrode potentials and reducing noise, thereby improving the precision of distance calculations in TOF-based systems.
Implementation Method 1
a light-receiving element... detects reflected light
Implementation Method 2
a transistor that suppresses a change in the potential of the electrode of the light-receiving element
Implementation Method 3
a time-of-flight (TOF) method... light travel time delay that occurs between the emitted light and the reflected light is detected
Data Source
AI summary
A distance measurement device with high detection accuracy. The distance measurement device includes a photosensor including a light-receiving element, a first transistor, and a second transistor; a wiring; a signal line; and a power supply line. The wiring is electrically connected to one electrode of the light-receiving element. The signal line is electrically connected to a gate electrode of the first transistor. The power supply line is electrically connected to one of a source electrode and a drain electrode of the second transistor. One of a source electrode and a drain electrode of the first transistor is electrically connected to a gate electrode of the second transistor. The other of the source electrode and the drain electrode of the first transistor is electrically connected to the other electrode of the light-receiving element and the other of the source electrode and the drain electrode of the second transistor.