Acousto-optic deflectors allow the creation of multiple optical traps by time-sharing, that is, by rapidly cycling the laser focus between designated spatial locations. The traps thus formed are not permanent. Here, we successfully demonstrate the creation of multiple and permanent traps by means of acousto-optic deflectors driven by specially encoded RF signals. The generation of complex acoustic signals allows us to treat such devices as super-fast spatial light modulators. Using this technique, it is possible to generate several static optical trap arrays and switch them at kilohertz (kHz) rates, allowing independent control of each trap group. Additionally, we discuss the compatibility of this method with precise force and position measurements and the improvement in their frequency bandwidth compared to time-sharing optical tweezers, especially when many objects are trapped.

Two methods for assessing the image quality of optical systems based on the analysis of wavefront aberration (WA) are presented together. The methods and the experimental setups are broadly described. A comparative study between those two techniques on the analysis of a meniscus lens has been carried out and an equivalence between both techniques has been tested and demonstrated, by comparing the RMS associated to their measured Zernike coefficients.

Using the context of Galileo Galilei´s pioneering observations of the Saturn's rings, the students are driven to build an optical telescope in the laboratory and analyze and discuss the different solutions to improve its resolution.

Using the context of Galileo Galilei´s pioneering observations of the Saturn's rings, the students are driven to build an optical telescope in the laboratory and analyze and discuss the different solutions to improve its resolution.1 The JavaOptics Course (JOptics) is an ensemble of Java applets and teaching resources for Physical Optics courses at university level for Physics of Optics and Optometry courses. The Course was developed by the members of the Optics and Photonics Research Group of the Applied Physics Department of the Universitat de Barcelona in the early 2000's thanks to three projects (DOGC-3453, 2003MQD-00138 and 11/III/MM-Eva/34/CARN) and the use of its resources for educational purposes is open and free. It consists of a series of 13 Java applets that covers all the topics of a Physical Optics course, from Geometrical Optics and Colorimetry, to Fourier Optics and Optical Tweezers.