Ocean Optics USB Spectrometer Indirect Sampler

thingiverse

A compact enclosure for color measurements that snugly fits an Ocean Optics USB2000/USB2000+/USB4000 spectrometer and employs an Opteka white balance card to direct light into the spectrometer through variable apertures. The enclosure is printed with black, opaque filament and features extra perimeters to minimize stray light interference. Flexible TPU material is used for retaining bands, while clear filament is chosen for diffusers. A standard set of parts includes at least one aperture piece, a sampler body, a sampler cover, two large retaining bands, and one small retaining band. Tips for usage: Incoming light is restricted by apertures in the specified order, with maximum open being 100% and minimum being domed diffused. However, the angle of incoming light plays a lesser role as you move down the list. Open apertures can produce significant differences with varying angles, but smaller ones are less effective at shining directly on the spectrometer input, whereas diffused ones exhibit better performance. If attenuation or angle rejection is required, choices can be made among available options, and an additional component can fit within the housing. When the spectrometer's slit is too wide or the light source is excessively intense, an 18% grey balance card can be used instead of a white balance card to provide further attenuation. Aperture percentages are determined by the area of the opening (a 39mm diameter circle), allowing for ratiometric use – for instance, the 100% opening has double the aperture of the 50% opening hole and ten times that of the 10% hole in square millimeters.