From 0-24:00 on February 27, 2022, 36 new cases were added in Shenzhen, including 30 confirmed cases of new coronary pneumonia and 6 cases of asymptomatic infection of the new coronavirus. Among them, 27 cases were found in close contacts under centralized isolation and observation, 8 cases were found in nucleic acid screening in key areas, and 1 case was found in nucleic acid screening in key population groups. The continued existence of the new crown epidemic has also made us more aware of the importance of the pharmaceutical and medical equipment industries. In the pharmaceutical and medical device industries, machine vision inspection technology is often used for quality control in high-volume manufacturing environments. For example, in the production of medical products such as syringes and vials, machine vision is often used for quality inspection.

In the pharmaceutical and medical device industries, machine vision can start from inspecting raw materials, all the way to inspecting finished products and their packaging. Product inspection can include size, shape, color, integrity, etc., as well as the presence of defects or foreign objects. Packaging inspection includes everything from checking the fill level of vials and bottles, to filling blister packs. It also detects the presence and location of tamper-evident seals, as well as other details about package integrity. It is also important to confirm the presence of labels, as well as to read and verify 1D/2D codes and human readable text. Using a serialized QR code on each package can be traced back to production from the point of sale. Machine vision lighting is an important part of ensuring accurate and repeatable measurements when performing all of these tasks.

Machine vision lighting needs to provide the illumination intensity and uniformity required by the application in order to generate images with good contrast and signal-to-noise ratios to highlight features of interest. These characteristics are determined by the application itself. Factors such as the color, surface texture, shape, and reflectivity of the object being imaged all affect its interaction with light, which also determines which light source form and wavelength are best suited for a particular inspection task. The geometrical position between the object, the light source and the camera determines the orientation, the angle of illumination and the angle at which the camera collects the light.

       What are the requirements for the light sources needed by pharmaceutical and medical manufacturers? High-speed, high-volume production requires precise pulses to "freeze" motion in the image. High illumination intensity is required to clearly capture small target information on moving objects, such as 1D and 2D codes. Lighting used in clean room environment, the heat generation should be small to prevent product aging. Maintain a stable level of illumination intensity and uniformity to ensure good manufacturing practice. Many pharmaceutical powders need to be tested for foreign matter before they are compressed into tablets. Conventional dome illumination provides uniform illumination of the powder, and wavelengths can be selected to provide the best contrast between powder and contamination. Foreign objects in the vial-filled solution can be identified by detecting the liquid using high-intensity directional illumination from a spotlight located at the bottom of the vial. Some opaque liquids may be transparent to infrared light, so infrared illumination can be used to reveal contaminants.

Dirt or other surface defects on tablets can also be detected using a high-angle ring light that provides bright spot illumination. Light from surface textures and features, such as scratches and imperfections, bounce off the camera, so they appear as dark features on a bright background. The low-angle ring light provides darkfield illumination that highlights surface features because the camera only picks up light scattered by surface imperfections. A major problem facing package inspection is reflections from the packaging material, which makes it difficult to obtain acceptable images, especially when the package surface is uneven. Traditional dome and flat dome lights provide even, diffuse illumination to minimize glare and shadows, making uneven surfaces appear flat, enabling the imaging of codes and text printed on packaging. Flat dome lights produce the effect of a dome light in a thin housing package, do not require a hole for the camera, and take up less space than a dome light. In addition, the choice of wavelength is also critical to enhance the contrast of the print against the background.