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We build an experiment of optical tweezers based on the use of an inverted optical microscope for manipulating microsized single crystals, which are made of an organic dye and parallelepiped in shape. The microcrystals are directed so that their long axis is in the axial direction of the trapping beam. Their short axis follows the direction of the linear polarization of the beam. In circular or elliptic polarization, the crystals are spontaneously put in rotation with a high speed of up to 500 turns per second. It is the first time, to the best of our knowledge, that such a result is reported for particles of the size of our crystals. Another surprising result is that the rotation speed was first increased as expected by increasing the incident power, but after passing by a maximum it decreased until the complete stop of rotation, whereas the power continued growing. This evolution was not reversible. Several hypotheses are discussed to explain such behavior.

In study of dynamic processes, information on parameters of system can be obtained from the changes in corresponding dynamic speckle pattern. Examples of these processes are biological, chemical or biochemical reactions, changes in molecular populations, changes in absorption, reflection properties or refraction index of a medium, superficial dynamics process, crystal dissolution, particle movement and others. In the present work the generation and counting of pulses corresponding to signals obtained from dynamic speckle patterns, and a study of some signal processing methods, in particular the analysis of pseudo-phase portrait are shown.

As science advances, it is more evident the necessity of a health interdisciplinary approach in Medicine. In the case of medical applications of light, the knowledge of the use of dispositives, equipment, diagnostic and treatment means, as well as the bases for the use of this update technologies is required. At the present moment, the outstanding work of specialized professionals of different profiles requires personnel with high professional formation in keeping with the latest trends in science and technology. The authors present here an Specialized Project in Biophotonics, with the aim of increasing the professional preparation of university graduates with an ample profile--physicists and engineers--who work in Biomedical Optics, thus contributing to the specialized formation of medic and paramedic personnel. The course is structured into six-subject-modules and into two phases. As to the basic professional formation, each one attending this course, will select between two variants of the Basic Formation Postgraduate Course: Anatomy and Physiology, Physical Bioenergetics, Clinic Bioenergetics; or Physics in Medicine, Optics and Applied Information Theory, depending on the student's professional profile. In the second phase, the General Formation Postgraduate Course: Biomedical Optics, Optical Bioenergetics and Laser in Medicine.

About forty university graduates have completed their specialized studies in Optics. These specialized studies enable their successful development in their professional tasks in national Cuban institutions. In the conception of the Optics Master of Science degree plan, professional improvement is considered regarding the accumulated experience, the training requirements of human resources, as well as the contemporary world development trends.

The Laboratory of Coherent Optics possesses the following lines of investigation laser material processing, holography, image processing, biomedical applications of laser, speckle techniques and other optical measuring techniques. In the present paper, some of the most important results obtained in the last three years are described.