The approach dentistry to dental care is gradually shifting to a model focused on early detection and oral-disease prevention; one of the most important methods of prevention of tooth decay is opportune diagnosis of decay and reconstruction. The present study aimed to introduce a procedure for early diagnosis of tooth decay and to compare result of experiment of this method with other common treatments. In this setup, a laser emitting infrared light is injected in core of one bifurcated fiber-optic and conduced to tooth surface and with the same bifurcated fiber the radiation reflected for the same tooth is collected and them conduced to surface of sensor that measures thermal and light frequencies to detect early signs of decay below a tooth surface, where demineralization is difficult to spot with x-ray technology. This device will can be used to diagnose tooth decay without any chemicals and rays such as high power lasers or X-rays.
The possibility of using lasers diodes and a fiber optic trifurcated for the evaluation of the power optic absorbed on coals samples is studied. The method is based on scanning of samples using lasers diodes with the wavelengths 632,8nm, 532nm, 405nm, and calibration plots of the reflected luminosity of the selection as function of the absorbance of coals. In this paper we showed the calibration plots and the colorimetric parameters of coals calculated from the absorption or diffuse-reflectance. The advantages of the method are its high performance for estimating the colorimetric parameters of coals samples, quality control of industrial processes and classification of coals.
The avocado is a one climacteric fruit that not ripe on the tree because it produces a maturation inhibitor that passes the fruit through the pedicel, the ripening occurs naturally during storage or to be induced as required. In post-harvest ripening stage is basically determined by experience of the farmer or buyer. In this word us developed portable equipment for determining ripeness is hass avocado using a low cost sensor color sensor TC3200 and LCD for display result. The prototype read of RGB color frequencies of the sensor and estimates the stage of ripeness in fourth different stages in post-harvest ripening.
Nowadays, research in the field of science education points to the creation of alternative ways of teaching contents encouraging the development of more elaborate reasoning, where a high degree of abstraction and generalization of scientific knowledge prevails. On that subject, this research shows a didactic alternative proposal for the construction of Fresnel and Fraunhoffer diffraction concepts applying the Fourier transform technique in the study of electromagnetic waves propagation in free space. Curvature transparency and Fourier sphere operators in paraxial approximation are used in order to make the usual laborious mathematical approach easier. The main result shows that the composition of optic metaxial operators results in the discovery of a simpler way out of the standard electromagnetic wave propagation in free space between a transmitter and a receptor separated from a given distance. This allows to state that the didactic proposal shown encourages the construction of Fresnel and Fraunhoffer diffraction concepts in a more effective and easier way than the traditional teaching.
This paper develops and implements, can experimental method to characterize the process of splice optical fibers by fusion for determine the quality thereof. The procedure utilizes the Bragg diffraction law, allowing spectrally decomposed emitted light in the fusion splicing process. The experimental mounting used a diffraction grating to refract light, a video camera that allows capturing the image sequences during the complete process of fusion splicing, later and with the aid of the computational tool MATLAB is performed all the segmentation process, filtering, correlation and analysis of images obtained.
Taking into account that the Gabor transform is the Fourier transform of the multiplication of the transfer function of a system with the Fourier transform of the input signal to the system, was developed and implemented digital and optically a system that achieves optical Gabor transform, if we consider the situation when the spectral transfer function becomes very narrow and applies to images this technique will enable one to overcome the instrumental limitations of the optical system, reaching superresolution.
The dynamic speckle analysis has been done because speckle interference began to be evaluated as an important source of information, especially those related to biological samples under laser beam. The biospeckle is a phenomenon produced naturally when biological material is illuminated by laser light. If it is possible to record the temporal history of the phenomenon, it will be possible to identify, in a seed, areas with different activity. Biospeckle or dynamic speckle can be used as a method for analysing activity, biologic or not, from materials illuminated with laser beam. The Spatial Temporal Speckle (STS) contains data of time information of dynamic speckle and it is used as input for many techniques allowing the analysis of the activity which is being monitored. This paper presents the results of analysing biospeckle data using fractional order Fourier transform, coefficient filtering and reconstruction, with a novel approach to increase the information obtained.
It developed a system capable of recognizing of regular geometric figures, the images are taken by the software automatically through a process of validating the presence of figure to the camera lens, the digitized image is compared with a database that contains previously images captured, to subsequently be recognized and finally identified using sonorous words referring to the name of the figure identified. The contribution of system set out is the fact that the acquisition of data is done in real time and using a spy smart glasses with usb interface offering an system equally optimal but much more economical. This tool may be useful as a possible application for visually impaired people can get information of surrounding environment.
This paper shows the design and implementation of a fiber optic sensor for detecting and identifying wavelengths in the visible range. The system consists of a diffuse optical fiber, a conventional laser diode 650nm, 2.5mW of power, an ambient light sensor LX1972, a PIC 18F2550 and LCD screen for viewing. The principle used in the detection of the lambda is based on specular reflection and absorption. The optoelectronic device designed and built used the absorption and reflection properties of the material under study, having as active optical medium a bifurcated optical fiber, which is optically coupled to an ambient light sensor, which makes the conversion of light signals to electricas, procedure performed by a microcontroller, which acquires and processes the signal. To verify correct operation of the assembly were utilized the color cards of sewing thread and nail polish as samples for analysis. This optoelectronic device can be used in many applications such as quality control of industrial processes, classification of corks or bottle caps, color quality of textiles, sugar solutions, polymers and food among others.
This paper presents a simple method for manufacturing fiber tapered through elongation, by the combination of heating with a butane torch and controlled stretch. Reducing the diameter of the multimode fiber of 100 microns to 10 microns, the displacement of the fiber is performed through bipolar stepping motors with one driver L293B and one PIC16F628A microcontroller for controlling movement. The system allows control of the desired fiber diameter up to 10 microns; the results are seen in a microscope and a rule of separation 2.5μm micrometer to calculate the diameter of the fiber.
This paper presents the application of a fiber optic sensor based on bifurcated fiber bundles; in the bifurcated design,
separate fibers carry the excitation and emission radiation. The physics principle is simple, the fraction of light
transmitted between the receive elements in the bundle and the transmit elements in the bundles depends of the light
wave passes through the gasoline; three fuel-adulterant mixtures in different proportions by volume were prepared and
individually tested. The high sensitivity of laser, and the versatility of fiber-optic technology and experiment proved that
the system has simple construct and high sensitivity during absorption on a transition process.
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