HMD Luminance Control via Camera Feedback
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The accuracy of specifying the posture of a head-mounted display (HMD) using light-emitting units is reduced at low luminance, and increasing luminance increases power consumption, while existing methods require a separate device for luminance measurement to control drive current effectively.
Innovation Solution
A control apparatus with a posture specifying unit, luminance information specifying unit, and drive current control unit that uses a single camera image to specify the posture and luminance of light-emitting units, allowing for drive current control without a separate luminance measurement device, with the option to adjust luminance based on environmental brightness.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the luminance of the light-emitting units is increased to improve posture specification accuracy, then the accuracy of specifying the posture is improved, but the power consumption of the light-emitting units increases
Solution Approach 1:
The system uses a camera to capture images of the light-emitting units, specifies their luminance based on the captured images, and feeds this information back to control the drive current. This closed-loop feedback mechanism allows the system to maintain optimal luminance for posture specification accuracy while avoiding excessive power consumption by dynamically adjusting the drive current based on actual luminance measurements.
Solution Approach 2:
The camera that captures images for posture specification is also utilized to measure the luminance of the light-emitting units. This self-service approach eliminates the need for a separate luminance measurement device, allowing the system to monitor and control luminance using existing resources, thereby maintaining measurement accuracy without additional power consumption overhead.
2Use of energy by moving object
If the luminance of the light-emitting units is decreased to reduce power consumption, then the power consumption is reduced, but the accuracy of specifying the posture is reduced
Solution Approach 1:
The feedback mechanism continuously monitors the luminance of the light-emitting units using the camera and adjusts the drive current to maintain luminance within an optimal range. This ensures that the luminance is sufficiently high for accurate posture specification while being as low as possible to minimize power consumption, dynamically balancing these two competing requirements.
Solution Approach 2:
The system dynamically changes the drive current parameter based on the measured luminance to maintain optimal performance. By adjusting the drive current according to actual luminance conditions rather than using a fixed high value, the system maintains posture specification accuracy while reducing power consumption when high luminance is not necessary.
3Measurement precision
If a separate device for measuring luminance is provided to control drive current, then the luminance control accuracy is improved, but the device complexity increases
Solution Approach 1:
The camera is designed to serve multiple functions: capturing images for posture specification and measuring luminance of the light-emitting units. This multi-functionality allows the system to achieve accurate luminance control without adding a separate measurement device, thereby maintaining measurement precision while avoiding increased device complexity.
Solution Approach 2:
The luminance measurement function is merged with the existing camera system used for posture specification. By combining these two functions into a single device, the system achieves accurate luminance measurement and control without the complexity of a separate measurement device, reducing the overall system complexity while maintaining measurement accuracy.
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
This solution maintains optimal luminance of light-emitting units for posture specification while reducing power consumption by controlling drive current based on measured luminance, eliminating the need for a separate measurement device and improving accuracy in bright environments.
Implementation Method 1
an HMD including a plurality of light-emitting units, such as light-emitting diodes (LEDs), that emit light at luminance according to drive current
Data Source
Figure 1
Figure 2A~2B
Figure 3~4
AI summary
In a head-mounted display including a light-emitting unit for specifying a posture, control of luminance of the light-emitting unit is enabled without separately providing a device for measuring the luminance of the light-emitting unit. A posture specifying unit (62) specifies a posture of an HMD including a light-emitting unit that emits light at luminance according to drive current, the posture specified based on a posture specifying image taken by a camera, the posture specifying image including an image of the light-emitting unit. A luminance information specifying unit (64) specifies information indicating the luminance of the light-emitting unit based on a luminance specifying image taken by the camera that takes the posture specifying image, the luminance specifying image including an image of the light-emitting unit. A drive current control unit (66) controls the drive current of the light-emitting unit based on the specified information indicating the luminance of the light-emitting unit.