Imaging Lens Vibration Reduction via Perpendicular Lens Shift

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Macro imaging lenses face challenges in maintaining optical performance and correcting image blur caused by hand movements, especially at close object distances, due to increased aberrations and reduced aperture size, which leads to motion blur and increased influence of hand movements.

Innovation Solution

The design incorporates a specific arrangement of lens units with positive and negative refractive powers, where the first, third, and fifth lens units do not move during focusing, while the second and fourth units move, and the fifth lens unit shifts perpendicular to the optical axis to correct image position, satisfying specific focal length conditions to maintain optical performance and reduce hand movement effects.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the aperture size is reduced to ensure depth of field in macro imaging, then the depth of field increases, but the shutter speed decreases and motion blur easily occurs

Engineering Contradiction:

Improvedepth of fieldVSAvoidshutter speed

Core Design Contradiction:

ReliabilityVSSpeed

Solution Approach 1:

The patent implements a vibration reduction mechanism that dynamically moves the fifth lens unit perpendicular to the optical axis in response to detected hand movements. This dynamic adjustment compensates for motion blur caused by reduced shutter speed, allowing the system to maintain both deep depth of field and adequate freezing of motion.

Inventive Principle:

Principle #15Dynamics

2Ease of operation

If focusing is performed by moving the first lens unit toward the object side, then focusing capability is achieved, but the working distance decreases

Engineering Contradiction:

Improvefocusing capabilityVSAvoidworking distance

Core Design Contradiction:

Ease of operationVSLength of moving object

Solution Approach 1:

The patent divides the focusing function across multiple lens units (first, second, and fourth lens units can move independently) rather than relying solely on the first lens unit. This segmentation allows the first lens unit to remain stationary during macro focusing, maintaining working distance while other units compensate to achieve focus.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Instead of moving the first lens unit toward the object side for focusing, the patent inverts the approach by moving subsequent lens units (second and fourth units) to achieve focusing while keeping the first lens unit stationary, thereby maintaining working distance.

Inventive Principle:

Principle #13The other way round (Inversion)

3Adaptability or versatility

If the object distance decreases for close-distance imaging, then macro imaging capability is achieved, but the influence of hand movements on the obtained image increases

Engineering Contradiction:

Improvemacro imaging capabilityVSAvoidinfluence of hand movements

Core Design Contradiction:

Adaptability or versatilityVSObject-affected harmful factors

Solution Approach 1:

The patent employs a vibration reduction mechanism that uses feedback from hand movement detection to control the position of the fifth lens unit. The system detects hand movements and adjusts the lens unit position in real-time to compensate, reducing the influence of hand movements on macro imaging results.

Inventive Principle:

Principle #23Feedback

Solution Approach 2:

The patent implements a dynamic vibration reduction mechanism that actively adjusts the fifth lens unit position in response to detected hand movements. This dynamic compensation allows macro imaging at close distances while minimizing the detrimental effects of hand movements through real-time correction.

Inventive Principle:

Principle #15Dynamics

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 configuration enables reliable correction of aberrations and spherical aberrations, maintaining good optical performance in both basic and vibration-reducing states, effectively reducing image blur caused by hand movements and ensuring stable macro imaging operations.

Implementation Method 1

The fifth-a lens unit moves in a direction having a component perpendicular to an optical axis to shift a image position

Methodology Applied

Scientific EffectOptical image position shifting:

Implementation Method 2

a first lens unit having a positive refractive power; a second lens unit having a negative refractive power; a third lens unit having a positive refractive power; a fourth lens unit having a positive refractive power; and a fifth lens unit having a negative refractive power

Methodology Applied

Scientific EffectRefraction: Refraction

Data Source

PatentUS7864451B2Imaging lens and image pickup apparatus including the same

Publication Date: 2011.01.04 CANON KK

AI summary

An imaging lens includes first to fourth lens units in order from the object side to the image side. The first, third, and fourth lens units have a positive refractive power. The second and fifth lens units have a negative refractive power. During focusing from an object at infinity to a close object, the first, third, and fifth lens units do not move, and the second and fourth lens units respectively move toward the image side and the object side. The fifth lens unit includes a fifth-a lens unit having a negative refractive power which moves in a direction having a component perpendicular to an optical axis to shift a image position, and a fifth-b lens unit having a positive refractive power. Focal lengths of the third lens unit, the entire system of the imaging lens, the fifth-a lens unit, and the fifth-b lens unit are adequately set.