US 5,940,176 A · Accurate manual illumination inspection

Abstract

A method and device for the accurate manual inspection of three-dimensional (not flat) samples, such as pharmaceutically injectable vials, for particle contamination, which samples are illuminated with diffused (non-point) light. Opposing vertically positioned and spaced illumination sources are provided above and below the vial, with the vial being positioned in an inspection volume at the illumination midpoint (lumen light balance) between the illumination sources. The illumination midpoint, for light sources of equal intensity, is also the physical midpoint therebetween. Though the mid-point is not the position of maximum illumination for light sources, normal variation in manual inspections, e.g., variations in inspector height and deviations caused by manual handling of the vial, at the mid-point, result in minimal deviations in illumination, with resulting greater accuracy and replicability of inspection results. The station further optionally includes a light-dark-light changeable background for inspection of different contrast particles which may be in the vial, without removal of the vial from the inspection point at the illumination midpoint.

Claims20

Dependent claims

A method for enhancing the reliability of an illuminated inspection of defects in three dimensional items in an inspection station wherein the inspection station comprises an illumination source positioned on one side of an inspection volume in which a three dimensional item is positioned, and which inspection volume is visually aligned with an inspector for inspection with illumination from the illumination source;

said method comprising the steps of:
a) providing a second illumination source on a second side of the inspection volume substantially directly opposite that of the first illumination source and substantially in line therewith;
b) substantially visually aligning the inspection volume with an illumination midpoint between the illumination source positioned on one side of the inspection volume and the second illumination source positioned on the side substantially opposite to the first illumination source relative to the inspection volume;
and
c) directly illuminating the three dimensional object with the respective illumination sources only with light therefrom which is in a substantially direct line between the respective illumination sources.

2 more elements

An inspection station for illuminated inspection of three dimensional items for defects therein, with enhanced reliability, wherein the inspection station comprises an illumination source positioned on one side of an inspection volume in which a three dimensional item is positioned, and which inspection volume is visually aligned with an inspector for human inspection with illumination from the illumination source;

characterized in that the inspection station further comprises a second illumination source on a second side of the inspection volume substantially directly opposite that of the first illumination source and substantially in line therewith;
wherein the inspection volume is substantially aligned with an illumination midpoint between the illumination source positioned on one side of the inspection volume and the second illumination source positioned on the side substantially opposite to the first illumination source relative to the inspection volume;
whereby there is direct illumination of the three dimensional object by the respective illumination sources only with light therefrom which is in a substantially direct line between the respective illumination sources.

Dependencies are inferred from the claim text.

Accurate manual illumination inspection

Life of this patent

Accurate manual illumination inspection

Life of this patent

Abstract

Claims20