By Jonathan Bry, Ackley Machine Corporation
What is a Fluorescence Vision System?
In-short, a fluorescence vision system is an automated inspection environment.
Why Is It Important?
Softgels have never been inspected for shell integrity, logo quality, leakers, fill-level, seam presence, and cross-linking, at the end of their labeling process – and yet they contain medicine! All of these factors affect not only the advertising logo of the manufacturer, they affect the performance of medicine delivery. It’s important to get on board with this now because regulations only increase as time goes on and are only added to products after it is proven that these things can be inspected. Regulations are driven by science and capabilities – not the other way around.
How Does Fluorescence Vision Work?
The reason this solid dosage has not been inspected in the past is because of difficulty in the most ubiquitous inspection method – visual inspection.
Typical Vision Inspection Workflow:
- Light source emitted from machine
- Emitted light bounces off of the solid dosage
- Light that bounces off the solid dosage and is detected by the sensor within the camera on the vision system
Softgels appear reflective, specular, translucent, or clear in a wider range than other solid dosages but the physical principle of light reflection is not used by Ackley’s seamless technology so it is not crippled by this shortcoming. The range of diffuse and specular reflections creates an image that is impossible to focus without saturating the camera sensor and losing data.
Ackley’s Seamless Technology Workflow:
- Short wavelength Light is emitted from the machine (at acceptable levels for regulation compliance)
- Solid Dosage converts the light into longer wavelength light due to material properties of the shell
- Solid Dosage emits longer wavelength light uniformly toward camera on vision system
- Filters on camera lens exclude all light except the uniform longer wavelength
Why Does This Work?
Regardless of the surface quality/finish, the constant concentration of fluorescent agents in pharmaceuticals yields a constant emitted intensity bounded by a material’s quantum yield. Which is consistent compared to the variations caused by specular reflection and translucence normally seen by “white light” imaging systems. By isolating this constant light intensity (which can be done since it is a different wavelength than the exciting light AND the ambient light) a consistent surface quality can be seen regardless of surface finish.
To learn more about Ackley’s advanced Fluorescence Inspection for Soft Gelatin Capsules and to find out if it’s right for your bulk products, contact our sales team today!
Jonathan Bry is a mechanical engineer at Ackley Machine Corporation, Moorestown, NJ.