Optical Target Recognition
The Optical Target Recognition (Option) comprises a camera system assembled to the print head as well as a software extension for the Nano-Plotter software.
Considering a typical drop diameter of 50 Microns the Nano-Plotter is well appropriated to apply Nanolitre amounts of liquid to target structures in the same range. However, the nozzle alignment above tiny targets may become challenging if attempted manually.
The Optical Target Recognition automatically detects small patterns such as microelectrodes, nanowells and microcantilevers. This enables the Nano-Plotter to precisely find positions and spot onto them (manual selection of points by clicking in the camera window is also possible).
The camera looks for two alignment marks (“Fiducials”) on each chip/substrate. Spotting positions can be defined relative to the alignment marks. Regular target patterns like arrays of small wells usually don’t require dedicated fiducials.
Basic Function of Target Camera
The fiducial pattern recognition camera allows both point-and-click definition of the spot layout in a live video image or automatic target recognition by image processing software.
The video shows how the alignment process works. The user needs to write a “spotting plan” in advance for each spot pooint.
1. Initially a precise offset measurement gives the exact distance between the camera axis and the drop trajectory of each dispenser.
2. Now the camera travels to each of the two alignment markers on each target substrate. Two pictures are taken of each target substrate.
3. The software calculates the coordinates for each spot point and completes the spotting run without any further user interaction.