Pulsed Laser Spectroscopy for Plastic Substance Identification

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods for identifying substances and additives in plastics using spectroscopy have limited resolution and selectivity, making reliable identification challenging, especially in recycling applications where precise differentiation between chemically similar substances is necessary.

Innovation Solution

A device and method utilizing a pulsed laser with picosecond or shorter pulse durations for irradiating materials, allowing for improved spectral resolution and selectivity through fluorescence lifetime analysis, enabling more precise and reliable identification of plastics and their additives.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If continuously radiating lasers are used for irradiation, then the device operation is simple, but the spectral resolution and selectivity are low

Engineering Contradiction:
Improvespectral resolutionVSAvoidlaser control complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent applies periodic action by using pulsed laser irradiation instead of continuous radiation. The laser emits light in periodic pulses with specific duration (nanosecond to femtosecond range), creating time-resolved spectral measurements that improve resolution and selectivity while maintaining operational simplicity through automated pulse timing control.

Inventive Principle:
Principle #19Periodic action

2Measurement precision

If pulsed laser with picosecond pulse duration is used, then spectral resolution and selectivity are improved, but the device complexity increases

Engineering Contradiction:
Improveidentification reliabilityVSAvoidlaser system complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent applies parameter changes by precisely controlling the pulse duration parameter of the laser in the nanosecond to femtosecond range. This parameter optimization enables high spectral resolution and selectivity for reliable substance identification, while the automated control systems manage the increased device complexity through standardized interfaces and integrated timing circuits.

Inventive Principle:
Principle #35Parameter changes

3Measurement precision

If shorter pulse duration is used, then the signal-to-noise ratio increases, but the energy consumption increases

Engineering Contradiction:
Improvesignal-to-noise ratioVSAvoidlaser energy consumption
Core Design Contradiction:
Measurement precisionVSUse of energy by moving object

Solution Approach 1:

The patent applies continuity of useful action by using high repetition rate pulsed laser irradiation. Although individual pulses are short (nanosecond to femtosecond), the high repetition rate ensures continuous sampling and accumulation of signal, maintaining high signal-to-noise ratio while distributing energy consumption over time, thereby managing overall energy usage efficiently.

Inventive Principle:
Principle #20Continuity of useful 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

The use of pulsed lasers with picosecond or shorter pulse durations enhances the spectral resolution and selectivity of spectroscopic analysis, improving the reliability and flexibility of substance identification, particularly in recycling plastics, allowing for better differentiation between chemically similar substances and increasing the signal-to-noise ratio.

Implementation Method 1

a laser for irradiating a sample of the material with light of at least one wavelength, a detector for detecting the light re-emitted by the sample

Methodology Applied
Scientific EffectFluorescence: Fluorescence

Implementation Method 2

the laser is a pulsed laser which has a pulse duration in the range of picoseconds or an even shorter pulse duration

Methodology Applied
Scientific EffectFluorescence lifetime analysis: Fluorescence

Data Source

PatentEP3497431A1Device and method for identifying substances of a material by means of spectroscopy
Publication Date: 2019.06.19 KRIEG GUNTHER

AI summary

The invention relates to a device (1) for identifying substances of a material by means of spectroscopy, comprising a laser (2) for irradiating a sample (3) of said material with light of at least one wavelength, a detector (6) for detecting the light re-emitted by the sample, and an analysis device for the spectroscopic analysis of the detected light, said laser being a pulsed laser having a pulse duration in the picosecond range or even shorter.