In recent years the Mexican government has modified the educational programs to include different subjects. Analyzing the natural science books we can notice that in the different units the themes are taught in a direct way introducing in every concept the relation with the everyday life of the students. Optics themes are included in a very good way. The programs some teachers are facing now is that some of them do not have enough experience in this change so a training program has been establish to improve their skills to show them how to implement experiments about the theoretical concepts and to have a wider amount of experiment to enrich the subject.
Innovation through science and technology will be essential to solve important challenges humanity will have to face in the years to come, regarding clean energies, food quality, medicine, communications, etc. To deal with these important issues, it is necessary to promote STEM (Science, Technology, Engineering and Mathematics) education in children. In this work, we present the results of the strategies that we have implemented to increase the elementary and middle school students interest in science and technology by means of activities that allow them to use and develop their creativity, team work, critical thinking, and the use of the scientific method and the engineering design process.
Since 2005, it was decided in Mexico that children have to start their formal education at the age of 3 years, two years earlier that in many other countries. This change was done to increase activities that enhance the social interaction and stimulus (knowledge and skills) of the students to prepare them to the next academic level. The main drawback of the developed curriculum for the younger children is that it does not include enough scientific activities. The work presented here is the answer of a particular initiative of some teachers to implement scientific workshops in optics. We have found that preschoolers are attracted to scientific activities if the material is presented in the right way. While design any scientific activity it is important to remember that young children want to know about their world without changing it, they have to experience the principle without memorizing, therefore the language used to describe concepts, ideas or terms has to be carefully chosen to avoid confuse preschoolers that can lose track of the activity. The scientific information has to be very clear and limited to a single physical principle and the concepts have to be presented in a way to include games as a learning activity that allow them to experience with the results.
The original initiative or this program was from the Science Council of the State of Guanajuato, and it was extended thanks to the support of the SPIE grant. The outreach coordination supported the idea of visiting elementary schools that belong to remote municipalities or rural schools of the region; we have worked with communities from 30 to 300 miles apart from the city of León. The workshops to be given were chosen, taking into consideration that they needed to be really representative, creative, and demonstrative, useful and at the same time neither expensive nor delicate. The school were reached and in several occasions. At the moment, at least one request of workshops for communities is served every week, where approximately 5000 children had been attended in the last two years.
A spatial light modulator, using a liquid crystal display (LCD), has been developed to be implemented in a measurement system which is based on the heterodyne interferometry. This interferometric device can be applied to the study of the mean roughness of reflective objects and phase distributions in transparent objects. An infinite moving grating is simulated on the LCD spatial modulator, on a screen with 128 x 240 pixels, which is handled by a microcontroller program in which the direction and velocity of the displacement, and also the fill factor and spatial period, can be defined. We show our first experimental results using this modified heterodyne interferometer to measure the profile of transparent and reflective objects.
A holographic lens is recorded superimposing two beams with orthogonal linear polarizations on an azobenzene polymer film. The polarization pattern on the interference plane induces two modulations in the media: the volume and the surface modulation. The spatial frequency of the surface relief is twice the one for the volumetric modulation resulting in a holographic lens with two different focal lengths. Additionally, because of the modulated anisotropy induced in the medium, the polarization at the longer focus distance is orthogonal to the polarization at the shorter one. We propose this polarization element to send or detect information in two planes simultaneously or separately by using an analyzer behind the holographic lens.
A holographic study of films prepared with polyvinyl alcohol (PVA) with different molecular weights and sensitized by introducing a dye of the triphenylmethane group is reported. Interference patterns obtained from the superposition of parallel and orthogonal polarized beams are storage in the dyed palates. Recording dynamics of the resultant electric field distributions and dependence of the diffraction efficiency on the PVA molecular weight are determined. Additionally, it is demonstrated that reconstruction of the object polarization is dependent on the frequency of the polarization grating. Finally, the recording area of the material is analyzed to detect a relief formation.