Tunable Photo Detector Proximity Sensor with Periodic Detection

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Solution Overview

Problem

Current proximity sensors face challenges in accurately detecting target objects and determining their distance due to limitations in response time and power consumption, as well as inefficiencies in controlling the sensors to meet specific specifications.

Innovation Solution

A tunable proximity sensor system utilizing a photo detector with doped regions and control circuitry to manage voltage amplitudes, allowing the sensor to switch between non-detecting and detecting states, and synchronizing a pulsing light source with the photo detector to measure the time between light emission and current flow for object detection and distance calculation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the photo detector operates in continuous detection mode, then the detection capability is maintained, but the power consumption increases

Engineering Contradiction:
Improvedetection capabilityVSAvoidpower consumption
Core Design Contradiction:
ReliabilityVSUse of energy by moving object

Solution Approach 1:

The photo detector is operated in periodic detection cycles, alternating between a first state (detecting state) and a second state (non-detecting state). During the detecting state, the photo detector is enabled to detect incident light with high sensitivity. During the non-detecting state, the photo detector is disabled or placed in a low-power mode, significantly reducing power consumption. This periodic operation maintains detection capability when needed while minimizing energy consumption during intervals when detection is not required.

Inventive Principle:
Principle #19Periodic action

2Speed

If the photo detector response time is reduced to meet specifications, then the detection speed improves, but the power consumption increases

Engineering Contradiction:
Improveresponse timeVSAvoidpower consumption
Core Design Contradiction:
SpeedVSUse of energy by moving object

Solution Approach 1:

The system implements periodic detection cycles where the photo detector is activated only during necessary detection intervals. By switching the photo detector between active (detecting) and inactive (non-detecting) states, the system achieves fast response times when detection is required while minimizing power consumption during non-detection periods. This approach allows the photo detector to operate at full speed capability only when needed.

Inventive Principle:
Principle #19Periodic action

Solution Approach 2:

The operating state of the photo detector is dynamically adjusted based on detection requirements. The system transitions the photo detector between different operational states (detecting and non-detecting) depending on real-time needs. This dynamic state management allows the system to optimize the balance between response time and power consumption by activating fast-response mode only when detection is required.

Inventive Principle:
Principle #15Dynamics

3Use of energy by moving object

If the photo detector is placed in reverse bias mode to reduce current flow, then the power consumption decreases, but the detection sensitivity is reduced

Engineering Contradiction:
Improvepower consumptionVSAvoiddetection sensitivity
Core Design Contradiction:
Use of energy by moving objectVSReliability

Solution Approach 1:

The system periodically switches the photo detector between a detecting state (with full sensitivity) and a non-detecting state (with reduced sensitivity or disabled). During the detecting state, the photo detector operates with optimal bias conditions for maximum sensitivity. During the non-detecting state, the photo detector is placed in reverse bias mode or disabled, reducing current flow and power consumption. This periodic alternation maintains high detection sensitivity when needed while achieving power savings during intervals when detection is not required.

Inventive Principle:
Principle #19Periodic action

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 system effectively detects the presence and distance of target objects with improved response times and power management, enabling precise control over the sensor's operating state to meet response time and power consumption specifications.

Implementation Method 1

the light absorbing region includes at least one material in which, in response to light incident thereon, carrier pairs of opposite charge are generated

Methodology Applied
Scientific EffectPhotoelectric Effect: Photoelectric Effect

Data Source

PatentEP3020075B1Proximity sensor systems and their operating methods
Publication Date: 2018.09.05 ACTLIGHT
  • EP3020075B1 patent drawingFigure 1
  • EP3020075B1 patent drawingFigure 2
  • EP3020075B1 patent drawingFigure 3

AI summary

Techniques for using photo detectors as tunable proximity sensors for detection of target objects and ascertaining their distance from the proximity sensors are disclosed. In one embodiment, the techniques may be realized as a proximity sensor system including a photo detector having a first doped region, a gate, a second doped region and a light absorbing region, a control circuitry for generating a plurality of control signals to be applied to the photo detector, and a signal detector to detect an output signal from the photo detector.