Optical Tracking Pointer for Autofocus Selection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional image pickup apparatuses face challenges in maintaining immediacy of cursor movement and preventing autofocus from being started unintentionally, particularly due to limitations in capacitance-type sensors and optical input devices that are prone to dust accumulation and finger slippage issues.

Innovation Solution

The design incorporates optical tracking pointers integrated into AF-ON buttons and shutter buttons, allowing for touch-based operations that enable immediate cursor movement and autofocus selection without finger movement between selection and activation, while also featuring a concave detection face to prevent dust accumulation and reduce finger slippage.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If a capacitance type sensor is used for optical input device, then the device can detect finger movement for cursor control, but it is difficult to increase the stroke in the pushing direction and may erroneously detect slight pushes as intentional input

Engineering Contradiction:
Improvedetection accuracyVSAvoidoperational reliability
Core Design Contradiction:
Measurement precisionVSEase of operation

Solution Approach 1:

The patent replaces the capacitance type sensor with an optical tracking pointer that uses optical fields instead of electrical fields to detect finger movement. This substitution allows for increased pushing stroke without erroneous detection, as the optical system tracks the actual position and movement of the finger rather than sensing changes in capacitance that can be triggered by unintentional contact.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

2Object-affected harmful factors

If the detection face is made convex to prevent dust accumulation, then dust collection is reduced, but finger slippage is increased which deteriorates finger guide performance

Engineering Contradiction:
Improvedust accumulationVSAvoidfinger slippage
Core Design Contradiction:
Object-affected harmful factorsVSEase of operation

Solution Approach 1:

The patent applies different surface qualities to different regions of the detection face. The finger guide face has a convex shape to prevent dust accumulation, while the contact surface has a concave shape to reduce finger slippage. This local differentiation allows each region to optimize for its specific function without compromising the other.

Inventive Principle:
Principle #3Local quality

3Ease of operation

If the detection face is made concave to reduce finger slippage, then finger guide performance is improved, but fine dust tends to collect in the center portion which interferes with fingerprint detection

Engineering Contradiction:
Improvefinger slippageVSAvoiddust accumulation
Core Design Contradiction:
Ease of operationVSObject-affected harmful factors

Solution Approach 1:

The patent inverts the conventional approach by making the finger guide face convex rather than concave. This inversion prevents dust accumulation in the finger guide region while the concave contact surface is positioned where it won't collect interfering dust. The inversion of the finger guide face shape resolves the contradiction between preventing slippage and preventing dust collection.

Inventive Principle:
Principle #13The other way round (Inversion)

4Device complexity

If operation member such as joystick or dial is used for selecting autofocus position, then the device structure is simple, but the cursor cannot be moved to the target focus position quickly requiring multiple operations

Engineering Contradiction:
Improveoperation member structureVSAvoidtime to move cursor
Core Design Contradiction:
Device complexityVSLoss of time

Solution Approach 1:

The patent replaces mechanical operation members like joysticks and dials with an optical tracking pointer system. This substitution allows the cursor to be moved directly to the target focus position by simply pointing the finger at the desired location on the detection face, eliminating the need for multiple incremental operations while maintaining a relatively simple device structure.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

5Ease of operation

If touch pad is used for selecting autofocus position, then the cursor can be moved according to finger movement maintaining immediacy, but another operation member is required to start autofocus requiring finger movement between selection and activation

Engineering Contradiction:
Improvecursor movement immediacyVSAvoidtime to start autofocus
Core Design Contradiction:
Ease of operationVSLoss of time

Solution Approach 1:

The patent merges the cursor movement function and the autofocus activation function into a single integrated operation. The optical tracking pointer both moves the cursor to the desired position and activates autofocus when the finger is placed on the detection face, eliminating the need for separate operation members and reducing the time required to start autofocus while maintaining cursor movement immediacy.

Inventive Principle:
Principle #5Merging (Combining)

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 ensures uninterrupted and precise cursor movement and autofocus selection, reducing the risk of unintended autofocus activation and minimizing dust-related interference, thereby enhancing user experience and operational efficiency.

Implementation Method 1

an optical tracking pointer as an optical input device having a detection face (contact surface) provided in succession with the finger guide face. Since the detection face to which the finger contacts so that the fingerprint is read

Methodology Applied
Scientific EffectOptical reflection: Reflection

Data Source

PatentEP3879338B1Imaging apparatus and electronic equipment that have optical input device
Publication Date: 2024.02.28 CANON KK
  • EP3879338B1 patent drawingFigure 1A~1B
  • EP3879338B1 patent drawingFigure 2A~2B
  • EP3879338B1 patent drawingFigure 2C~2D

AI summary

The immediacy is not reduced, and autofocus is not started while the focus position being selected. The image pickup apparatus includes an operation member that selects a position for performing autofocus using a light input device that detects the movement of the finger and instructs the start of autofocus by an operation by the finger. When autofocus being performed, a display object for selecting a position for performing autofocus is displayed on the display unit 28 and the viewfinder in-field display unit 41. The system control unit 50 moves the display object according to the movement amount of the finger detected by the light input device, and starts autofocus at the position of the display object when the operation member is operated. The light input device is disposed below the face, of the operation member, on which the finger is placed.