Tianjin University's Photoacoustic Remote Sensing Microscopy Technology Breakthrough New Heights

Recently, Professor Tian Zhen's team from Tianjin University has made a breakthrough in the field of photoacoustic remote sensing microscopy technology and successfully developed a new type of non-destructive testing method. This technology uses Kaplin high-power femtosecond laser as the key light source, further optimizing the solution to the internal flaw detection limitations of inverted chips, improving the overall detection performance of the system, and opening a new chapter for the development of non-destructive testing technology.

Leading the way and promoting a leap in non-destructive testing technology
Photoacoustic remote sensing microscopy technology, as a promising detection microscopy method proposed in recent years, can achieve a large field of view and fast non-destructive testing imaging inside inverted chip models. It is of great significance for the detection of high-value analytes such as chips and biological tissues.

Researchers introduce that traditional microscopy techniques often face the dilemma of difficult to balance imaging depth and resolution. Either the imaging depth is not high, such as OCT; Either the resolution is not high and there is contact. Photoacoustic remote sensing microscopy technology can significantly solve these pain points, achieving characteristics such as large imaging depth, high resolution, and non-contact, and has high value in medical applications.

In the research, Tianjin University used a Kaiprin 20 watt infrared femtosecond laser as the femtosecond laser source, providing stable and high-quality laser pulses for photoacoustic remote sensing microscopes. The output center wavelength of the laser is 1030 nm, the repetition rate is adjustable from 0.1 to 1 MHz, and the pulse width is adjustable from 300 fs to 10 ps (the pulse width used in the experiment is about 1.2 ps).

After collimation, beam expansion, and combined with a 1310 nm continuous probe light beam emitted by a superluminescent diode, it finally enters the optomechanical scanning system, which is a large field of view fast scanning imaging system composed of a galvanometer scanning mirror system, an objective lens, and a three-dimensional electric displacement stage. During the imaging process, the inverted chip is in an inverted state, meaning that the internal metal structure is not visible relative to the bright field microscope.

The photoacoustic remote sensing microscope system can perform large field optical mechanical joint scanning imaging on inverted chip models. Its working principle is to first obtain an independent small field of view through "mosaic scanning", then move the chip sample to the next adjacent position through an electric displacement table, and finally concatenate these small range images to form a complete large field of view image.. The experimental results fully demonstrate that photoacoustic remote sensing microscopy has the potential for non-destructive testing of chips in industrial environments.

The successful application of this technology will significantly improve the overall detection performance of the system and is expected to become an important tool for non-destructive testing in the medical field, providing strong support for early detection and precise treatment of diseases.

Femtosecond laser creates a powerful engine for scientific research and innovation
Keplen's high-power femtosecond laser provides strong support for scientific research fields such as photoacoustic remote sensing microscopy technology due to its excellent stability, adjustable pulse width, and good beam quality.

This 20 watt infrared femtosecond laser, thanks to its all fiber structure and industrial integration design, demonstrates excellent stability and processing capabilities. Its characteristics include long-term continuous processing stability, adjustable pulse width, repetition rate, and adjustable pulse energy, which control the pulse time domain within 300 femtoseconds, effectively reducing the thermal impact on material processing and achieving true "cold" processing.

This laser is widely favored in the field of organic thin film and flexible material processing, and has also attracted attention in the domestic ultrafast laser market. It not only handles flexible and brittle materials such as OLED, glass, ceramics, sapphire, semiconductor materials, and alloy metals, but also plays an important role in micro/nano processing, precision marking, and other precision machining applications.

Writing on "hair strands", ultrafast lasers can showcase their skills. The head of Keplen's ultrafast business unit stated that ultrafast lasers have enormous development potential, not only continuously expanding human cognitive boundaries in cutting-edge fields, but also continuously overcoming key technological challenges in application fields. Looking ahead to the future, Keplen will uphold a long-term philosophy, deeply cultivate the fields of femtosecond, picosecond, and nanosecond lasers, provide more innovative solutions for scientific research and industrial applications, and promote the progress and development of technology.

Source: Kaplin