Display Power Supply Wake Control Using Human Presence Detection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing power supply systems struggle to automatically cancel power saving modes when a person is present, requiring manual user intervention to switch back to normal operation.

Innovation Solution

A power supply device and display apparatus that include a power supply unit, acquisition unit, first and second determination units, and a control unit to automatically cancel power saving mode based on detection results from a human presence sensor and user operations, allowing for intelligent mode switching.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If the human presence sensor keeps detecting a person after power saving mode is set, then the detection accuracy is improved, but the mode switching cannot be canceled automatically requiring manual user intervention

Engineering Contradiction:
Improvedetection accuracyVSAvoidmode switching convenience
Core Design Contradiction:
Measurement precisionVSEase of operation

Solution Approach 1:

The system performs preliminary action by disabling the human presence sensor for a predetermined period after power saving mode is activated. This prevents the sensor from detecting persons during the period when users are likely to approach the device, thereby avoiding unnecessary mode cancellations and eliminating the need for manual intervention to maintain power saving mode.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The system dynamically adjusts the operational state of the human presence sensor based on the power supply mode. The sensor is disabled during the predetermined period after power saving mode activation, and can be re-enabled later based on system state, creating a dynamic adaptation that resolves the contradiction between detection accuracy and operational convenience.

Inventive Principle:
Principle #15Dynamics

2Ease of operation

If the power saving mode is canceled immediately upon detecting a person, then the usability is improved, but the power consumption increases unnecessarily

Engineering Contradiction:
ImproveusabilityVSAvoidpower consumption
Core Design Contradiction:
Ease of operationVSUse of energy by moving object

Solution Approach 1:

The system applies preliminary action by pre-disabling the human presence sensor during the predetermined period after power saving mode activation. This prevents false detections that would trigger unnecessary mode cancellations, thereby maintaining power saving mode longer and reducing unnecessary power consumption while still allowing immediate response when truly needed.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The system uses feedback from the power supply mode state to control the human presence sensor operation. By monitoring whether the device is in power saving mode and adjusting sensor activation accordingly, the system creates a feedback loop that optimizes both usability and power consumption by avoiding premature mode cancellations.

Inventive Principle:
Principle #23Feedback

3Speed

If the human presence sensor is always active, then the responsiveness to user presence is improved, but the power consumption increases

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

Solution Approach 1:

The human presence sensor operates dynamically based on the power supply mode. In normal mode, the sensor is active to detect user presence. In power saving mode, the sensor is disabled for a predetermined period to reduce power consumption. This dynamic adaptation allows the system to maintain responsiveness when needed while conserving energy during power saving operation.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The system changes the operational parameter of the human presence sensor (active/inactive state) based on the power supply mode and elapsed time. This parameter change allows the sensor to be highly responsive during normal operation while consuming minimal power during power saving mode, resolving the contradiction between responsiveness and power consumption.

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentEP4293479B1Power supply device and display apparatus
Publication Date: 2026.02.25 RICOH CO LTD
  • EP4293479B1 patent drawingFigure 1
  • EP4293479B1 patent drawingFigure 2
  • EP4293479B1 patent drawingFigure 3

AI summary

A power supply device includes a power supply unit (200) to supply power to an information processing apparatus; an acquisition unit (301) to acquire a detection result of a person by a detection unit (6) disposed at the information processing apparatus, a first determination unit (302) to output a first determination result indicating whether a first condition is satisfied, a second determination unit (303) to output a second determination result indicating whether a second condition is satisfied, and a control unit (304) to cancel the power saving mode based on the first determination result and the second determination result in a case where the detection result indicates that a person is detected in a state where the information processing apparatus is in the power saving mode. In the power saving mode, the power supplied to the information processing apparatus is reduced as compared with a normal mode. The first condition relates to an operation receivable by the information processing apparatus, and the second condition relates to a situation around the information processing apparatus.