Abstract: A metal 3D printing device comprises a building platform, a first powder spreading arm, a second powder spreading arm, a gas stream unit and a scanning module. The building platform is for supporting the powder. The first and second powder spreading arms are spaced and configured for spreading powder. The gas stream unites comprises a gas blowing port and a gas suction port, the gas blowing port is provided in the first powder spreading arm, and the gas suction port is provided in the second powder spreading arm. The scanning module is for emitting a laser to the powder preplaced between the first and second powder spreading arms to solidify the powder to form the product.

Abstract: A light microscope comprises a light source and a first acousto-optic tunable filter responsive to the light source for producing two light streams of different polarization. A control circuit is provided for tuning the first filter to a plurality of frequencies. A mechanism, such as steering optics, is provided for combining the two light streams into a combined light stream. Input optics focus the combined light stream. A condenser, such as a darkfield condenser, receives the focused, combined, light stream and projects it onto a sample. A second acousto-optic tunable filter is responsive to light from the sample. A second control circuit is provided for tuning the second acousto-optic filter to a plurality of frequencies. The light from the second acousto-optic tunable filter may be captured and stored for future processing.

Abstract: An imaging system comprises an acousto-optic tunable filter for receiving light at an input end thereof and outputting light at an output end thereof. A control circuit is provided for tuning the filter. A prism is responsive to the light output by the tunable filter. The prism is oriented at an angle with respect to the filter to compensate for dispersion of the output light caused by the tunable filter.