Scanning Mirror Timing Encoding for Low-Bandwidth Display Links

Solution Overview

Problem

In scanning mirror display systems, transmitting both color and timing information uncompressed requires significant bandwidth and power, complicating system design, especially in wearable devices with limited resources.

Innovation Solution

Implementing a derivative-based encoding scheme for timing information, using a variable-length codebook to compress second derivatives, allowing for a much smaller number of bits to be used, thereby reducing bandwidth and power consumption.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If uncompressed timing information is transmitted for each light sample, then timing precision is maintained, but bandwidth consumption and power usage increase significantly

Engineering Contradiction:

Improvetiming precisionVSAvoidpower consumption

Core Design Contradiction:

Measurement precisionVSUse of energy by moving object

Solution Approach 1:

The patent extracts only the essential timing information by computing derivatives (differences) between consecutive light sample timings. Instead of transmitting full timing values, only the changes in timing are transmitted, which captures the necessary precision information while dramatically reducing data volume and power consumption.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent inverts the traditional approach by not transmitting absolute timing values directly. Instead, it transmits the differences (derivatives) of timing values, and the receiving system reconstructs the absolute timing by accumulating these differences. This inversion reduces the number of bits required while maintaining timing precision.

Inventive Principle:

Principle #13The other way round (Inversion)

2Loss of information

If uncompressed timing information is transmitted for each light sample, then complete timing data is available, but communication bandwidth requirements increase

Engineering Contradiction:

Improvetiming data completenessVSAvoidbandwidth efficiency

Core Design Contradiction:

Loss of informationVSProductivity

Solution Approach 1:

The patent extracts only the essential timing information by computing derivatives (differences) between consecutive light sample timings. Instead of transmitting full timing values, only the changes in timing are transmitted, which captures the necessary precision information while dramatically reducing data volume and power consumption.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent inverts the traditional approach by not transmitting absolute timing values directly. Instead, it transmits the differences (derivatives) of timing values, and the receiving system reconstructs the absolute timing by accumulating these differences. This inversion reduces the number of bits required while maintaining timing precision.

Inventive Principle:

Principle #13The other way round (Inversion)

3Measurement precision

If full precision timing information is transmitted using more bits, then timing accuracy is maintained, but system complexity and power consumption increase

Engineering Contradiction:

Improvetiming accuracyVSAvoidsystem complexity

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The patent extracts only the essential timing information by computing derivatives (differences) between consecutive light sample timings. Instead of transmitting full timing values, only the changes in timing are transmitted, which captures the necessary precision information while dramatically reducing data volume and power consumption.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent inverts the traditional approach by not transmitting absolute timing values directly. Instead, it transmits the differences (derivatives) of timing values, and the receiving system reconstructs the absolute timing by accumulating these differences. This inversion reduces the number of bits required while maintaining timing precision.

Inventive Principle:

Principle #13The other way round (Inversion)

Data Source

PatentUS11227520B1Derivative-based encoding for scanning mirror timing

Publication Date: 2022.01.18 MICROSOFT TECHNOLOGY LICENSING LLC

AI summary

One example provides, on a scanning mirror display system, a method for communicating timing information for light samples that are scanned to form a displayed image. The method comprises, for a line of light samples, encoding timing information for a first light sample of the line of light samples using a first, greater number of bits to form encoded timing information for the first light sample. The method further comprises encoding timing information for a subsequent light sample of the line of light samples by computing a derivative based upon a timing of the subsequent light sample compared to a prior light sample, encoding the derivative using a second, lesser number of bits to form encoded timing information for the subsequent light sample, and sending the information for the first light sample and the subsequent light sample across the communications channel.