1、 Basic principles

Laser confocal microscope uses a laser beam as a light source to form a point light source by illuminating a pinhole, scanning every point on the focal plane of the specimen. The scanning laser and fluorescence collection share the same objective lens, and the focus of the objective lens is the focal point of the scanning laser, which is also the object point for instantaneous imaging. In this way, by controlling the focusing depth, images of different depth levels of the sample can be obtained.

2、 Imaging process

Laser irradiation:

The laser beam passes through the illumination pinhole to form a point light source.

The point light source is reflected by a spectroscope to the objective lens and focused on the sample.

Fluorescence excitation and collection:

If there are fluorescent substances in the sample that can be excited, these substances will emit fluorescence after being irradiated by laser.

The emitted fluorescence is directly reversed back to the spectroscope through the original incident light path.

Confocal imaging:

Fluorescence is focused first when detecting pinholes, and only light on the focal plane can pass through the detection pinhole.

The focused light is detected and collected by a photomultiplier tube (PMT) or a cold coupled device (cCCD), and the signal is transmitted to a computer.

After processing the signal, the computer displays the image on the monitor.

3D imaging:

Obtain multiple confocal images by automatically moving the focus position.

By utilizing 3D reconstruction techniques, a three-dimensional image of the sample can be obtained.

3、 Technical features

High resolution: Laser confocal microscopy can achieve high-resolution imaging of samples and provide clear image information.

3D imaging capability: By acquiring multiple confocal images and performing 3D reconstruction, a three-dimensional image of the sample can be obtained.

Non invasive: Laser confocal microscopy does not require slicing of the sample or introduction of exogenous contrast agents, avoiding damage to the sample.

High precision measurement: Laser confocal microscopy can also be used to accurately measure information such as sample size, shape, and surface morphology.

4、 Application Fields

In the industrial field, laser confocal microscopy is mainly used in the following areas:

Material testing: used to detect internal defects, cracks, delamination, and other issues in materials to ensure their quality.

Workpiece testing and measurement: used to measure the size, shape, and surface morphology of workpieces to ensure their accuracy and performance.

Coating and connection quality assessment: used to evaluate the uniformity and thickness of coatings, as well as the quality of connection joints.

In summary, the working principle of laser confocal microscopy in the industrial field is based on laser scanning confocal technology, which achieves imaging and measurement of samples through steps such as laser irradiation, fluorescence excitation and collection, confocal imaging, and three-dimensional imaging. This technology has the characteristics of high resolution, 3D imaging capability, non-invasive and high-precision measurement, and has broad application prospects in material detection, workpiece testing and measurement, as well as coating and connection quality evaluation.