Fiber Sensor Grip Detection for Cryogenic Sample Exchange

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Charged particle beam devices, such as electron microscopes, face challenges in detecting whether a sample holding member is properly gripped during sample exchange, leading to uncertainties in observing and storing samples, especially when samples are cooled to extremely low temperatures.

Innovation Solution

A sample exchange device equipped with a grip portion, fiber sensors, and a control unit that detects whether the grip portion is holding the sample holding member in the sample exchange chamber, allowing for precise detection and handling of samples within the chamber.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If a magazine is used to transport multiple samples to the sample exchange chamber at one time, then sample storage and re-observation capability are improved, but the ability to detect whether a cartridge is properly attached to the magazine is lost

Engineering Contradiction:

Improvesample transport efficiencyVSAvoidcartridge attachment detection accuracy

Core Design Contradiction:

ProductivityVSMeasurement precision

Solution Approach 1:

The patent replaces mechanical detection methods with optical detection using a fiber sensor. The fiber sensor emits light and detects changes in light reception based on the presence or absence of a cartridge, providing precise non-contact detection without mechanical complexity.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The fiber sensor acts as an intermediary between the magazine system and the control unit. It converts the physical state of cartridge attachment into optical signals that can be processed by the control unit, enabling indirect but accurate detection.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Reliability

If samples are cooled to liquid nitrogen temperature to preserve sample structure, then sample integrity is improved, but detection and handling of sample holding members becomes difficult

Engineering Contradiction:

Improvesample structure preservationVSAvoidsample handling difficulty

Core Design Contradiction:

ReliabilityVSEase of operation

Solution Approach 1:

The patent uses optical detection (fiber sensor) instead of mechanical contact methods to detect the sample holding member. This allows detection without mechanical interaction that could be problematic at cryogenic temperatures, maintaining both sample integrity and operational capability.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The fiber sensor automatically detects the presence or absence of the cartridge through optical means, eliminating the need for manual checking or complex mechanical sensors that would require maintenance at low temperatures.

Inventive Principle:

Principle #25Self-service

3Measurement precision

If a fiber sensor is continuously operated to detect cartridge presence, then detection reliability is improved, but heat transfer to the cold sample environment increases

Engineering Contradiction:

Improvecartridge detection reliabilityVSAvoidsample exchange chamber temperature

Core Design Contradiction:

Measurement precisionVSTemperature

Solution Approach 1:

The fiber sensor is operated periodically rather than continuously. The control unit activates the fiber sensor only at appropriate moments in the sample exchange cycle, reducing heat input while maintaining detection capability when needed.

Inventive Principle:

Principle #19Periodic action

Solution Approach 2:

The fiber sensor detects cartridge presence before transport operations begin, allowing the system to prepare accordingly. This preliminary detection avoids unnecessary continuous operation and reduces overall heat exposure to the cryogenic environment.

Inventive Principle:

Principle #10Preliminary action

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

Enables reliable detection and handling of sample holding members, ensuring smooth transportation and storage of samples, even at low temperatures, while preventing heat transfer and maintaining the sample's integrity.

Implementation Method 1

a fiber sensor that detects whether or not the grip portion of the first transport mechanism grips the sample holding member in the sample exchange chamber

Methodology Applied

Scientific EffectLight detection: Photoelectric Effect

Implementation Method 2

a cooling unit that cools the sample exchange chamber

Methodology Applied

Scientific EffectCryogenic cooling: Cryogenics

Data Source

PatentUS11205558B2Sample exchange device and charged particle beam device

Publication Date: 2021.12.21 JEOL LTD

AI summary

A sample exchange device includes a first transport mechanism that includes a grip portion that grips a sample holding member and transports a sample holding member to a sample exchange chamber, a cooling unit that cools the sample exchange chamber, fiber sensors that detect whether or not the grip portion of the first transport mechanism grips the sample holding member in the sample exchange chamber, and a control unit. The control unit turns on the fiber sensors when the grip portion of the first transport mechanism enters the sample exchange chamber and turns off the fiber sensors after it is detected whether or not the grip portion of the first transport mechanism grips the sample holding member.