Optical Sensor Clock Calibration via Communication Signal Feedback

Solution Overview

Problem

Conventional optical sensor devices experience significant clock frequency deviations due to temperature or pressure variations, particularly when using low-power or low-cost oscillators, affecting operations such as frame timings and image processing.

Innovation Solution

An optical sensor device with an oscillator circuit and processor that dynamically calibrates the clock signal based on parameters like time intervals and data lengths of communication signals from a monitoring system, allowing for adjustments to maintain accurate frequency without external notification from the monitoring system.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by stationary object

If a low power or low-cost oscillator is used in the clock generator, then power consumption and cost are reduced, but clock frequency accuracy deteriorates with significant deviations up to 20 percent

Engineering Contradiction:

Improvepower consumptionVSAvoidclock frequency accuracy

Core Design Contradiction:

Use of energy by stationary objectVSMeasurement precision

Solution Approach 1:

The optical sensor device performs self-calibration by automatically detecting frequency deviations through communication signals from the monitoring system and adjusting its clock generator accordingly. This self-service mechanism eliminates the need for external calibration notifications while maintaining accurate timing despite using low-power oscillators.

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The system establishes a feedback loop where the optical sensor device measures the frequency deviation of its clock signal by comparing timing information from communication signals with the monitoring system. Based on this feedback, the device automatically adjusts the clock generator to compensate for deviations caused by temperature or pressure variations.

Inventive Principle:

Principle #23Feedback

2Ease of manufacture

If a low power or low-cost oscillator is used in the clock generator, then cost is reduced, but clock frequency accuracy deteriorates with significant deviations up to 20 percent

Engineering Contradiction:

ImprovecostVSAvoidclock frequency accuracy

Core Design Contradiction:

Ease of manufactureVSMeasurement precision

Solution Approach 1:

The optical sensor device performs self-calibration by automatically detecting frequency deviations through communication signals from the monitoring system and adjusting its clock generator accordingly. This self-service mechanism eliminates the need for external calibration notifications while maintaining accurate timing despite using low-power oscillators.

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The system establishes a feedback loop where the optical sensor device measures the frequency deviation of its clock signal by comparing timing information from communication signals with the monitoring system. Based on this feedback, the device automatically adjusts the clock generator to compensate for deviations caused by temperature or pressure variations.

Inventive Principle:

Principle #23Feedback

3Reliability

If clock frequency deviates significantly, then operations such as frame timings and image processing are affected, but adding complex calibration mechanisms increases device complexity

Engineering Contradiction:

Improveoperation accuracyVSAvoidcalibration mechanism complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The calibration mechanism leverages the existing communication interface between the optical sensor device and the monitoring system. The same communication channel used for data transmission is also utilized for calibration purposes, eliminating the need for separate calibration hardware or protocols and reducing overall device complexity.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The optical sensor device performs self-calibration by automatically detecting frequency deviations through communication signals from the monitoring system and adjusting its clock generator accordingly. This self-service mechanism eliminates the need for external calibration notifications while maintaining accurate timing.

Inventive Principle:

Principle #25Self-service

Data Source

PatentUS20230299937A1Optical sensor devices and method capable of calibrating clock signal by itself when receiving one or more transmissions of specific communication signal from monitoring system

Publication Date: 2023.09.21 PIXART IMAGING INC

AI summary

A method of an optical sensor device includes: using an oscillator circuit to generate a clock signal; and generating monitoring frames according to the clock signal; wherein the clock signal is calibrated in response to at least one of: a first communication signal, transmitted for multiple times from a monitoring system externally coupled to the optical sensor device, is received by the optical sensor device; a data length of the first communication signal transmitted for only one time from the monitoring system externally coupled to the optical sensor device; and, a data length of an encoded data portion of the first communication signal transmitted for only one time.