Proveris Technical Note – TN0106
SprayVIEW Laser Verification
The Proveris Scientific SprayVIEW® Measurement System helped to establish the industry standard for automated spray pattern and plume geometry measurements for orally inhaled and nasal drug products (OINDP). We have since worked to expand the platform’s capabilities to include Plume Front Velocity (PFV) measurement, as well as Evaporation Fraction measurement. At its
core, the SprayVIEW consists of a Vereo® Automated Actuator used to fire the device in testing, a laser light source used to illuminate the spray from the device, and a high speed camera used to capture a series of images from the spray event. Those images are then analyzed using proprietary algorithms in order to produce data for the measurement in question. Just like in any other form of photography, lighting is everything!
In order to properly illuminate the spray from a particular device, the SprayVIEW uses a specially selected semiconductor laser with custom optics in order to create a fanned planar beam that allows for illuminating cross sections of a spray (see Figure 1). In order to produce repeatable and accurate data, it is essential that the laser continues to operate within spec with the key factor to be measured being the power of the laser across the field of illumination. Since the data generated is dependent on the pixel intensity seen by the camera at different points on the spray pattern or plume, illuminating the entire spray with constant, uniform power is necessary to be able to draw conclusions from the data.
Figure 2. SprayVIEW Laser Verification Kit
Please note that the digital meter is a calibrated tool and must be recalibrated annually by the manufacturer. Proveris can facilitate this calibration service and we generally recommend sending the meter back to us for calibration immediately before any annual maintenance on the system is performed by a Proveris engineer. Since laser verification is performed as part of the preventative maintenance procedure, the meter can be sent back to us prior to its scheduling and will be returned to the user in a few weeks, leaving plenty of time to perform the next verification as per the recommended frequency.