Single Slit Diffraction Pattern Research Articles

University students’ recognition of typical wave optics patterns

The recognition and distinction of typical interference and diffraction patterns are among the expected learning outcomes of studying wave optics. Previous studies have reported high school students’ difficulties with this task. In this study, we investigated university students’ ability to distinguish typical wave optics patterns obtained by the double slit, single slit, and diffraction grating. We also used eye tracking to obtain an insight into the distribution of students’ visual attention during the task. The results showed that university students had similar difficulties in recognizing wave optics patterns as high school students. They mostly struggled with identification of the double-slit interference patterns and diffraction grating patterns of monochromatic light while they were more successful in recognition of the diffraction pattern of white light on an optical grating and single-slit diffraction patterns. The eye-tracking data also revealed that students spent more time attending colourful than grey patterns in questions regarding diffraction of white light on an optical grating, thus suggesting that they were aware that the diffraction grating separates white light into colours. In questions regarding monochromatic light patterns, students overall mostly attended the single-slit diffraction pattern probably because of its distinct central maximum. Furthermore, the longer fixation duration for patterns compared to the text implies that students found it easier to extract information from the text than from the patterns. No prior research has compared the number of transitions during problem solving with the accuracy of the answers. In this study, we observed that students who incorrectly solved a task demonstrated a significantly higher number of gaze transitions between the question and the options, as well as among different options. The results of this study indicate that the recognition of typical wave optics patterns is also difficult for university students, thus suggesting that more attention should be paid to systematic observation and identification of key features of basic wave optics phenomena in lecture demonstrations and student laboratories.

Single slit diffraction pattern of Schrödinger particle with interaction with the wall

Single slit diffraction pattern of Schrödinger particle with interaction with the wall

Logger Pro for the Observation of Single-Slit Diffraction in the Determination of Metal Coefficients of Linear Thermal Expansion

Experiments using Logger Pro-aided observation of single-slit diffraction patterns have been performed to determine coefficients of linear thermal expansion of metals. The sample metals were iron and brass. The calculation involves weighted linear regression analysis of 1/z against temperature, where z is the distance between the end to the center of the central bright line, and a computer-aided χ2 goodness of fit test. From the χ2 goodness of fit test, it is concluded that the relation between 1/z and temperature is linear, in agreement with theory. The coefficients of linear thermal expansion for iron obtained agree well with the reference value, while that for brass is close to the reference values.

Seeking missing pieces in learning about single slit diffraction: results from a teacher survey

Single slit diffraction is part of many high-school physics curricula throughout the world. In this study, we aimed to investigate whether high-school physics teachers from Bosnia and Herzegovina, Serbia and North Macedonia are adequately prepared to discuss with their students about various aspects of the single slit diffraction pattern, particularly about vertical length of diffraction fringes. To that end we conducted a written survey which included 57 high-school physics teachers. Besides asking teachers about students’ difficulties in learning about single slit diffraction, we also asked them to specify their own difficulties with this topic and required them to solve a conceptual task. Almost every second teacher believed that vertical length of diffraction fringes can be increased by changing shape or width of the slit and only 1 out of 57 teachers managed to correctly answer why diffraction fringes become shorter when we move away from the central maximum. We concluded that physics teacher education programmes should be changed to develop understanding of both, horizontal and vertical aspects of the diffraction pattern. To that end it is useful to provide learning opportunities which encourage combining ray and wave model of light.

Pseudo-Double-Slit Experiment with Two Glass Plates

We have demonstrated both interference and diffraction of a pseudo-double slit using two glass plates with a width and a length of about 5 cm and a thickness of about 5 mm. The plates are attached at the upper and lower ends with Scotch tape of about 0.1 to 0.3 mm between the plates. By adjusting the angle between the two plates, we are able to demonstrate a single-slit diffraction pattern or a double-slit interference pattern. Also we can simulate a changing separation between slits by changing the angle between the plates.

Student recognition of interference and diffraction patterns: An eye-tracking study

Previous studies have demonstrated that students have difficulties in applying the wave model of light to explain single-slit diffraction and double-slit interference patterns. In this study, we investigated if students could recognize typical interference and diffraction patterns at all. Eye movements of high-school students were measured while they were identifying patterns produced by monochromatic light on a double slit, single slit, and diffraction grating, and by white light on a diffraction grating. Most students had difficulties with recognizing double-slit interference pattern and diffraction grating pattern of monochromatic light. Identification of the single-slit diffraction pattern was easier probably due to its distinguishable central maximum. The easiest task for students was recognizing the diffraction pattern of white light on an optical grating. Eye-tracking data suggested that even students who incorrectly answered this question were aware that the diffraction grating separates white light into colors. Additionally, eye tracking revealed that students who identified patterns correctly attended more the correct pattern than other options, thus corroborating previous findings. Overall, the results indicate that the recognition of interference and diffraction patterns is quite demanding for students, suggesting that more attention should be paid to observing and understanding basic wave optics phenomena.

A Simple Way to Teach Single Slit Diffraction Based on Edge Diffraction

Young’s experiment is hailed as a milestone in ushering a new understanding of the wave nature of light and is even taught at the high school level. Unfortunately, even the most cursory presentation of the subject of diffraction becomes confusing. The theory and equations based on Fresnel’s work appear arcane and incomprehensible to a high school student. In addition, students are not taught the significance of a phenomenon that has been observed since the time of Thomas Young: the bright band of light at the center of every single slit diffraction pattern. This paper presents a simple way to introduce the subject of diffraction based on Thomas Young’s original work and explains how the interplay of different components of diffracted waves from a single slit creates the broad central maximum.

Diffraction of Einstein–Podolski–Rosen states with one- and two-copies

We investigate the single slit diffraction pattern of one- and two-pairs of photons obtained from spontaneous parametric down conversion. Our experimental setup generates two classes of states, Einstein–Podolski–Rosen states and near-separable states. For the first class of states the diffraction pattern is anomalous, and is explained by the quantum correlations observed in the transversal position–momentum degree of freedom of down converted photons. The diffraction pattern, associated with the second class of states is similar to the pattern obtained from a classical light source.

Speckle Patterns with Atomic and Molecular de Broglie Waves

We have developed a nozzle source that delivers a continuous beam of atomic helium or molecular hydrogen having a high degree of transverse coherence and with adequate optical brightness to enable new kinds of experiments. Using this source we have measured single slit diffraction patterns and the first ever speckle-diffraction patterns using atomic and molecular de Broglie waves. Our results suggest fruitful application of coherent matter beams in dynamic scattering and diffractive imaging at short wavelength and with extreme surface sensitivity.

Single-slit diffraction patterns of sub-nanometre-wavelength synchrotron radiation

The single-slit diffraction patterns of monochromatic X-rays of wavelengths 0.16 nm and 0.1 nm have been recorded on a large linear scale by using a long distance, 16 m, between slit and photographic plate. The spacings of subsidiary maxima ranged from 0.1 mm to 0.6 mm, depending upon the width of the slit. Applications of such diffraction patterns in illumination systems for X-ray phase contrast microscopy and interferometry are envisaged.

Diffraction pattern intensity measurements in the introductory college physics laboratory using microcomputers

Measurement of the intensity variations in a single slit diffraction pattern formed by a laser beam is made by means of a photoresistor detector interfaced with an Apple II-plus microcomputer through the paddle (game controller) connection. The computer programs, written in BASIC and assembly language, enable the student to (1) determine quantitatively the intensity of the maxima and minima; (2) see the intensity pattern as the data is acquired; (3) obtain a hard copy of the intensity plot observed on the screen monitor; and (4) compare the experimental and theoretical intensity patterns.

Diffraction effects on angular response of x-ray collimators

Angular responses have been measured for x-ray collimators with half-widths ranging from minutes of arc down to 10 arcsec. In the seconds-of-arc range, diffraction peaks at off-axis angles can masquerade as side lobes of the collimator angular response. Measurements and qualitative physical arguments lead to a rule of thumb for collimator design; namely, the angle of first minimum in the Fraunhofer single-slit diffraction pattern should be less than one-fourth of the collimator geometrical full-width at half-maximum intensity.

Numerical methods for solving two transcendental equations which appear in Fraunhofer diffraction

The intensity distribution in a Fraunhofer single-slit diffraction pattern is described by transcendental equations of the form x=C sinx and x=C tanx. The first equation appears in the solution for the width of the central maximum of the pattern. The second results from an attempt to locate the positions of the secondary maxima. Students who are used to explicit (closed) solutions of equations are often distressed by the apparent need for trial-and-error methods. Graphical solutions give a good ’’feel’’ for the situation, but are not satisfying to those who would like greater precision. Numerical methods, which rely only on introductory calculus, can be easily applied. Algorithms employing pocket calculators are presented.

Diffractographic Dynamometer

A recent paper has described a new diffractographic sensor utilizing a changing single slit diffraction pattern to determine torque in rotating or stationary shafts (T. R. Pryor, O. L. Hageniers, and W. P. T. North, Soc. Exp. Stress Anal., in press). In that experiment, diffraction pattern fringe spacing was visually measured and found linearly related to torque. Described here isa simple and useful modification to the above device that produces a pulse burst whose frequency is linearly proportional to horsepower. Such a n output is quasi-digital and preserves the high resolution and other advantages previously obtained. Another version, producing a pulse burst whose count is linearly proportional to torque, is also discussed. The principal disadvantage of the disclosed electronic horsepower readout is a small dead zone of near zero values that cannot be measured.

The production of a single slit diffraction pattern by reflection

The production of a single slit diffraction pattern by reflection

Experimental Study of the Slit Function of an Ebert Spectrometer in the Visible and Near-Infrared*

The slit function of an Ebert spectrometer has been measured with different f numbers at the wavelength of the 0.5461 μ Hg line and the 2.05 μ He line. It is shown that the slit function changes from a single slit diffraction pattern to a Gaussian and finally to a triangular function for increasing slit width.

Determining the Positions of Maximum Intensity in the Single-Slit Diffraction Pattern

Determining the Positions of Maximum Intensity in the Single-Slit Diffraction Pattern