Moving Object Observation via Spatially Modulated Interference Imaging

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing observation apparatuses face difficulties in easily observing moving objects due to misalignment between the imaging plane and the object plane, leading to challenges in focus adjustment and observation.

Innovation Solution

An observation apparatus and method that splits light into first and second split light, spatially amplitude modulates the first split light with a modulation pattern to include varying wavenumber components, combines the split lights, and generates a complex amplitude image using an imaging unit and processing unit to align with the moving object's coordinate system.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the imaging plane is positioned at a location different from the object plane, then light interference can be performed, but focus adjustment becomes difficult and observation is not easy

Engineering Contradiction:
Improveinterference performanceVSAvoidfocus adjustment
Core Design Contradiction:
ReliabilityVSEase of operation

Solution Approach 1:

A lens is introduced as an intermediary optical element between the object plane and the imaging plane. This lens acts as a mediator that transforms the light field, enabling interference to occur at the imaging plane while maintaining optical conjugacy with the object plane, thus resolving the contradiction between interference capability and focus adjustment ease

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent introduces a spatial frequency dimension through the lens transformation. By mapping spatial coordinates in the object plane to spatial frequencies in the imaging plane, the system enables interference analysis while maintaining direct optical conjugacy, effectively adding a dimensional transformation that resolves the positioning contradiction

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Reliability

If the imaging plane is positioned at a location different from the object plane, then light interference can be performed, but observation of the observation object becomes difficult

Engineering Contradiction:
Improveinterference performanceVSAvoidobservation accuracy
Core Design Contradiction:
ReliabilityVSDifficulty of detecting and measuring

Solution Approach 1:

The lens serves as an intermediary that preserves optical conjugacy between the object plane and imaging plane. This ensures that the imaging plane remains optically linked to the object, maintaining observation accuracy while enabling interference to be performed at the imaging plane for reliable measurement

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The system creates an optical copy of the object field at the imaging plane through the lens transformation. This copy maintains the spatial information and optical conjugacy relationship, allowing accurate observation and measurement while enabling interference analysis on the copied field

Inventive Principle:
Principle #26Copying

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

Facilitates easy observation of moving objects by generating clear, aligned images and refractive index distributions, overcoming focus adjustment issues and enhancing observation accuracy.

Implementation Method 1

a modulation unit for spatially amplitude modulating the first split light based on a modulation pattern, and causing the first split light to include a plurality of light components having wavenumber components in a moving direction of the observation object different from each other

Methodology Applied
Scientific EffectSpatial amplitude modulation: Phase Modulation

Implementation Method 2

performs heterodyne interference between the first split light and the second split light

Methodology Applied
Scientific EffectHeterodyne interference: Interference

Implementation Method 3

combines the first split light which is Doppler shifted by being passed through the moving observation object and the second split light obtained by shifting an optical frequency by a heterodyne frequency

Methodology Applied
Scientific EffectHeterodyne: Heterodyne

Implementation Method 4

combines the first split light which is Doppler shifted by being passed through the moving observation object

Methodology Applied
Scientific EffectDoppler shift: Doppler Effect

Data Source

PatentEP4715367A1Observation device and observation method
Publication Date: 2026.03.25 HAMAMATSU PHOTONICS KK
  • EP4715367A1 patent drawingFigure 1
  • EP4715367A1 patent drawingFigure 2
  • EP4715367A1 patent drawingFigure 3

AI summary

An observation apparatus 1A is an apparatus for observing a moving observation object S, and includes a light source 11, a beam splitter 12, mirrors 13 and 14, a beam splitter 15, a modulation unit 21, lenses 31 to 34, an imaging unit 41, and a processing unit 42. The modulation unit 21 inputs first split light L1 arriving from the mirror 13, spatially amplitude modulates the input first split light L1 based on a modulation pattern, and causes the first split light to include a plurality of light components having wavenumber components in a moving direction of the observation object S different from each other. The processing unit 42 generates a complex amplitude image when the observation object S is irradiated with each of the plurality of light components based on a detection signal repeatedly output from the imaging unit 41. Thus, an apparatus capable of easily observing a moving observation object is realized.