Hamamatsu announces novel integration method for surface-emitting lasers...

28 Oct 2021

...and succeeds in medical diagnostic imaging without image reconstruction for the first time in the world.

Hamamatsu Photonics has established what it is calling high-density integration technology to create iPMSEL (integrable Phase Modulating Surface Emitting Laser) elements.

The company says these are the world’s smallest class semiconductor lasers capable of emitting light beams in 2D patterns. “By leveraging this technology, we succeeded in developing an iPMSEL array consisting of 16 elements formed in four rows and four columns on a tiny chip measuring just 2 square millimeters,” says the launch statement.

Each iPMSEL element on the chip can be independently switched to emit light beams in various patterns making the array suitable for industrial 3D shape measurement systems. The array can also be used for boosting motion capture and facial recognition accuracy; and in compact, portable fiber scopes in medical and industrial fields.

The array consists of 16 iPMSEL elements, each a square of approximately 200 μm and formed at high density on a 2 mm square chip. The array emits light beams while switching their beam patterns by electrical control of each individual element.

Product overview and applications

The iPMSEL array is capable of emitting light beams in various patterns that can form over 10,000 dots, fringes or stripes, grids, characters, CG and images. Hamamatsu says it has already developed iPMSEL elements based on the photonic crystal surface-emitting laser, along with its hologram design and microfabrication technologies.

The photonic crystal surface-emitting laser utilizes the 2D photonic crystal (structure where microstructures are aligned in space equivalent to a wavelength of light) as a resonator which is developed by Prof. Noda’s group in Kyoto university.

The company adds, “The iPMSEL array we have currently developed performs high precision measurements such as a phase-shifting method, making it promising as a light source for industrial 3D shape measurement systems that require very high accuracy.”

The phase-shifting method is a technique for measuring the 3D surface shape of an object with high accuracy, by irradiating periodic 2D beam patterns onto the target object and analyzing distortions in the beam patterns that occur depending on the shape of the object.

The iPMSEL array can also be applied to motion capture and facial recognition to enhance their accuracy. “Additionally,” adds the company, “the tiny size and light weight achieved by high density integration technology will prove ideal for creating a vast product range including small, compact industrial fiber scopes and endoscopes for the medical field.”

A portion of this research and development work was supported by Japan Science and TechnologyAgency.

Medical diagnostic imaging – without image reconstruction

Hamamatsu has this week also announced the achievement of high-accuracy medical imaging without image reconstruction by utilizing a pair of detectors, and novel light detection and signal processing techniques, pictured, right.

The company stated that applying these successful research results “are a promising means to achieve a new medical imaging system that can make diagnoses from a compact setup with the same or greater accuracy than currently used radiation imaging systems such as positron emission tomography and computed tomography.”

This capability will help boost inspection efficiency for detecting diseased tissues or organs, such as from cancer, and also reduce the radiation exposure dose, alleviating the load on the patient and medical staff.

These research results were gained through a joint effort with a group led by Simon Cherry, a distinguished professor at UC Davis School of Medicine in the US, a group led by Professor Yoichi Tamagawa at University of Fukui in Japan, and with Professor Tomoyuki Hasegawa at Kitasato University in Japan. The major results were published in Nature Photonics.