The LCD screen of a laptop computer provides a broad, bright, and extended source of polarized light. A number of demonstrations on the properties of polarized light from a laptop computer screens are presented here.

Physics educators around the world often need reliable diagnostic materials to measure students' understanding of physics concept in high school. The purpose of this study is to evaluate a new diagnostic tool on High School Optics concept. Test of Conceptual Understanding on High School Optics (TOCUSO) consists of 25 conceptual items that measures…

When data with and without an optically active sample are acquired simultaneously while one manually rotates the analyser, the graph of the first signal versus the second one is an ellipse whose shape shows the phase shift between the two signals; this shift is twice the optical rotation. There is no need to measure the rotation of the analyser or…

This article provides a terminological framework to show the relationships among different types of visual deficits. It distinguishes between visual functions, which describe how the eye and the lower visual system function, and functional vision, which describes how a person functions. When visual functions are disturbed, the term "visual…

The aim of the current research is to characterize the conceptual flow processes occurring in whole-class dialogic discussions with a high level of interanimation; in the present case, of a high-school class learning about image creation on plane mirrors. Using detailed chains of interaction and conceptual flow discourse maps--both developed for…

Special events like science days, teacher's meetings and physics recruiting efforts require spectacular and, if possible, interactive experiments for the audience. Based on past experience with such events, we have gathered and present here a series of demonstration experiments in mechanics, optics, waves and electricity which are suitable, and…

Eye aberrations are commonly corrected by lenses that restore vision by altering rays before they pass through the cornea. Some modern promoters claim that pinhole glasses are better than conventional lenses in correcting all kinds of refractive defects such as myopia (nearsighted), hyperopia (farsighted), astigmatisms, and presbyopia. Do pinhole…

Nonlinear optics is generally first presented as an extension of conventional optics. Typically the subject is introduced with reference to a classical oscillatory electric polarization, accommodating correction terms that become significant at high intensities. The material parameters that quantify the extent of the nonlinear response are cast as…

An apparently unnoticed analogy between the torque-free motion of a rotating rigid body about a fixed point and the propagation of light in anisotropic media is stated. First, a new plane construction for visualizing this torque-free motion is proposed. This method uses an intrinsic representation alternative to angular momentum and independent of…

Single photons are used for fundamental quantum physics experiments as well as for applications. Originally being a topic of advance courses, such experiments are increasingly a subject of undergraduate courses. We provide interactive screen experiments (ISE) for supporting the work in a real laboratory, and for students who do not have access to…

Optic neuropathy is common in mitochondrial disorders, but poorly characterized in Friedreich's ataxia (FRDA), a recessive condition caused by lack of the mitochondrial protein frataxin. We investigated 26 molecularly confirmed FRDA patients by studying both anterior and posterior sections of the visual pathway using a new, integrated approach.…

Incandescent lamps with tungsten filaments have been in use for about a century while being gradually replaced by fluorescent lamps; in another generation both will quite probably be largely replaced by light-emitting diodes. Incandescent lamps (simply called "lamps" in what follows) burn out after a lifetime that depends mostly on the temperature…

A historical discussion of the theories which deal with the formation of real images in mirrors and lenses is presented in this paper. Speculations on mirrors appeared as early as Plato. Euclid's, Hero's and Ptolemy's approaches to visual rays are described. The theory on burning mirrors starts with Diocles and later was continued by the Arabs. Al…

We describe the construction and operation of three low-cost schlieren imaging systems that can be fabricated using surplus optics and 80/20, an aluminium extrusion based construction system. Each system has a different optical configuration. The low cost and ease of construction makes these systems highly suitable for high-school and…

The measurement of solar UV under water is not a simple process. In the underwater environment the difficulty of obtaining useable data is greatly amplified due to the optically complicated and at times unpredictable nature of water itself. The following practical exercise designed for use in the Year 11 and Year 12 Physics classroom aims to…