Pulse Detection and Imaging Systems Using AC-DC Signal Segmentation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current imaging systems face challenges in simultaneously detecting short duration light sources, such as laser pulses, while maintaining imaging capability, particularly due to high input capacitance which increases noise in detectors and readout integrated circuits (ROICs).
Innovation Solution
The implementation of a device with an input circuit that separates detector signals into alternating current (AC) and direct current (DC) components, where the AC component is directed to a pulse detection circuit and the DC component to an imaging integration circuit, allowing for simultaneous imaging and pulse detection modes. This includes a buffered direct injection (BDI) circuit to isolate detector capacitance from the imaging integration circuit, reducing noise and enabling detection of short duration light sources.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If detector signals are processed by a single integration circuit for imaging, then imaging capability is maintained, but short duration light sources like laser pulses cannot be detected
Solution Approach 1:
The detector signal is segmented into two separate processing paths: an AC path for pulse detection and a DC path for imaging. The AC path uses a pulse detection circuit with a pulse detection capacitor to capture short duration light sources, while the DC path uses an imaging integration circuit for continuous imaging. This segmentation allows both functions to operate simultaneously without interference.
2Productivity
If detector capacitance is directly connected to the imaging integration circuit, then imaging is performed, but noise performance deteriorates due to high input capacitance
Solution Approach 1:
The signal processing is segmented into AC and DC paths. The AC path with pulse detection capacitor handles high-frequency pulse signals, while the DC path with imaging integration circuit handles low-frequency imaging signals. This frequency-based segmentation isolates the high input capacitance effect to specific paths, allowing optimal performance in each.
Solution Approach 2:
The pulse detection capacitor acts as an intermediary element that selectively couples AC pulse signals to the pulse detection circuit while blocking DC imaging signals. This intermediary component enables the system to handle both signal types without the full impact of detector capacitance affecting both paths simultaneously.
3Productivity
If the system operates in imaging mode only, then high frame rate imaging is achieved, but pulse detection capability is lost
Solution Approach 1:
The readout circuit is segmented into parallel AC and DC processing paths that can operate independently or simultaneously. The AC path with pulse detection capacitor enables pulse detection mode, while the DC path with imaging integration circuit enables imaging mode. Both modes can be activated at the same time, providing versatile operation.
Solution Approach 2:
The readout circuit is designed with multi-functionality to perform both imaging and pulse detection operations. By incorporating both AC-coupled pulse detection circuitry and DC-coupled imaging integration circuitry, the system can adapt to different operational requirements and handle multiple types of optical signals through a single detector array.
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
Enables the detection of short duration light sources, like laser pulses, while maintaining a high frame rate for imaging, thereby providing situational awareness of a scene and identifying targeted locations, with improved noise performance and reduced parasitic noise contributions.
Implementation Method 1
a detector configured to detect electromagnetic radiation and generate a detection signal based on the detected electromagnetic radiation
Data Source
AI summary
Techniques are disclosed for facilitating pulse detection and imaging. In one example, a device includes a detector configured to detect electromagnetic radiation and generate a detection signal based on the detected electromagnetic radiation. The device further includes an input circuit configured to provide, based on the detection signal, a first signal and a second signal. The device further includes an imaging integration circuit configured to generate an image of at least a portion of a scene based at least in part on the first signal. The device further includes a pulse detection circuit configured to perform pulse detection to generate an indication of whether a pulse is detected in the portion of the scene based at least in part on the second signal. Related methods and systems are also provided.