Tilted Observation and 3D Measurement of Microneedles and Their Molds

Microneedles are used not just for medication such as anesthetization, insulin, vaccines, and hyaluronic acid; but also widely in the administration of solutions for non-medicinal cosmetic purposes.

Administration to multiple points at a shallow depth on the skin (the epidermis) is possible, differing from the use of a general hypodermic needle, which administers the medicine to a single point in the dermis or lower in the hypodermis. A corresponding advantage is that the solution can be administered easily and painlessly because the needles do not reach the dermis, which has many pain receptors.

Molding is one typical microneedle production method. Mold management is vital in ensuring that each and every one of the many arranged microscopic needles is produced free of problems and defects.
However, molds have precise and complicated three-dimensional shapes, so with conventional microscopes it was necessary to use a jig to secure and tilt these small targets on the stage. It was also necessary to take a lot of time and effort to determine the lighting conditions due to the diffuse reflections of light characteristic to the metal material.

The VHX Series is equipped with an optical system and a 4K CMOS image sensor that combine high resolution with a depth of field that is at least 20 times larger than general optical microscopes. The large depth of field allows entire three-dimensional targets to be brought into focus. In addition, the depth composition function can be used to easily capture images that are fully focused throughout the entire field of view, even when observing three-dimensional targets at high magnifications. Of course, this depth composition function can also be used during tilted observation.
Furthermore, this product is equipped with the Multi-lighting function, which automatically acquires the data of multiple images captured with omnidirectional lighting at the press of a button. Observation can be started immediately just by selecting the image that matches the purpose, which dramatically reduces the condition determination time required until now.
The high performance and diverse functions described above allow for easy and fast tilted observation with high-accuracy 4K images, even when observing the 3D shapes of microneedle molds.

The VHX Series allows not just for high-resolution observation, but also fast 3D shape measurement.
This product instantaneously composes the image from multiple images with varying focus positions, allowing it to display 3D images that even capture textures and surface roughness. The result is that the 3D image displayed on the screen can be rotated to any angle for observation without having to move the target on the stage or change the angle of the lens.
Furthermore, 3D measurements can be performed from the high-accuracy 3D information that has been acquired, and profile measurements can be performed simply by selecting a cross section with the mouse. Sub-micrometer level measured values can be acquired for 3D measurements, cross-section shapes, and surface irregularities of the delicate microscopic needles in a non-destructive, non-contact manner.