Students examine the structure and function of the human eye, learning some amazing features about our eyes, which provide us with sight and an understanding of our surroundings. Students also learn about some common eye problems and the biomedical devices and medical procedures that resolve or help to lessen the effects of these vision deficiencies, including vision correction surgery.

Students use simple household materials, such as PVC piping and compact mirrors, to construct models of laser-based security systems. The protected object (a "mummified troll" or another treasure of your choosing) is placed "on display" in the center of the modeled room and protected by a laser system that utilizes a laser beam reflected off mirrors to trigger a light trip sensor with alarm.

Junior Lab consists of two undergraduate courses in experimental physics. The courses are offered by the MIT Physics Department, and are usually taken by Juniors (hence the name). Officially, the courses are called Experimental Physics I and II and are numbered 8.13 for the first half, given in the fall semester, and 8.14 for the second half, given in the spring.The purposes of Junior Lab are to give students hands-on experience with some of the experimental basis of modern physics and, in the process, to deepen their understanding of the relations between experiment and theory, mostly in atomic and nuclear physics. Each term, students choose 5 different experiments from a list of 21 total labs.

In a hands-on way, students explore light's properties of absorption, reflection, transmission and refraction through various experimental stations within the classroom. To understand absorption, reflection and transmission, they shine flashlights on a number of preselected objects. To understand refraction, students create indoor rainbows. An understanding of the fundamental properties of light is essential to designing an invisible laser security system.

Elevation data from ICESats GLAS instrument is quite detailed, as can be seen in this close-up view of a profile that passes near the Banzare Coast in Antarctica. (The green elevation profile in this animation is exaggerated vertically by a factor of 10x for aesthetic purposes.)

This module describes how we implemented the inverse filter for the laser microphone

This animation starts with a false-color map of tree heights north of San Jose, Costa Rica, and changes to a close-up 3D cut-away of a section of the forest with simulated green canopy. Data from LVIS observations taken in March, 1998.

Students learn and use the properties of light to solve the following challenge: "A mummified troll was discovered this summer at our school and it has generated lots of interest worldwide. The principal asked us, the technology classes, to design a security system that alerts the police if someone tries to pilfer our prized possession. How can we construct a system that allows visitors to view our artifact during the day, but invisibly protects it at night in a cost-effective way?"

Through two classroom demos, students are introduced to the basic properties of lasers through various mediums. In the Making an Electric Pickle demonstration, students see how cellular tissue is able to conduct electricity, and how this is related to various soaking solutions. In the Red/Green Lasers through Different Mediums demonstration, students see the properties of lasers, especially diffraction, in various mediums. Follow-up lecture material introduces students to the mechanisms by which lasers function and relates these functions to the properties of light. In the associated activity, student teams research specific laser types and present their findings to the class.

Create a laser by pumping the chamber with a photon beam. Manage the energy states of the laser's atoms to control its output.

Students research particular types of lasers and find examples of how they are used in technology today. Teams present their findings by means of PowerPoint presentations, videos or brochures. The class takes notes on the presentations using a provided handout. This activity prepares students for the "go public" phase of the legacy cycle in which they solve the grand challenge by designing and producing a laser-based security system.

This video segment adapted from A Science Odyssey uses a laser beam to demonstrate how light particles act like waves, illustrating Heisenberg's Uncertainty Principle.

Discover what controls how fast tiny molecular motors in our body pull through a single strand of DNA. How hard can the motor pull in a tug of war with the optical tweezers? Discover what helps it pull harder. Do all molecular motors behave the same?

Did you ever imagine that you can use light to move a microscopic plastic bead? Explore the forces on the bead or slow time to see the interaction with the laser's electric field. Use the optical tweezers to manipulate a single strand of DNA and explore the physics of tiny molecular motors. Can you get the DNA completely straight or stop the molecular motor?

Optical and optoelectronic properties of semiconductors, ceramics, and polymers. Electronic structure, refractive index, electroluminescence, electro-optic and magneto-optic effects, and laser phenomena. Microphotonic materials and structures; photonic band gap materials. Materials design and processing for lasers, waveguides, modulators, switches, displays and optoelectronic integrated circuits. Alternate years. This course covers the theory, design, fabrication and applications of photonic materials and devices. After a survey of optical materials design for semiconductors, dielectrics and polymers, the course examines ray optics, electromagnetic optics and guided wave optics; physics of light-matter interactions; and device design principles of LEDs, lasers, photodetectors, modulators, fiber and waveguide interconnects, optical filters, and photonic crystals. Device processing topics include crystal growth, substrate engineering, thin film deposition, etching and process integration for dielectric, silicon and compound semiconductor materials. The course also covers microphotonic integrated circuits and applications in telecom/datacom systems. Course assignments include three design projects that emphasize materials, devices and systems applications.

Optical and optoelectronic properties of semiconductors, ceramics, and polymers. Electronic structure, refractive index, electroluminescence, electro-optic and magneto-optic effects, and laser phenomena. Microphotonic materials and structures; photonic band gap materials. Materials design and processing for lasers, waveguides, modulators, switches, displays and optoelectronic integrated circuits. Alternate years. This course covers the theory, design, fabrication and applications of photonic materials and devices. After a survey of optical materials design for semiconductors, dielectrics and polymers, the course examines ray optics, electromagnetic optics and guided wave optics; physics of light-matter interactions; and device design principles of LEDs, lasers, photodetectors, modulators, fiber and waveguide interconnects, optical filters, and photonic crystals. Device processing topics include crystal growth, substrate engineering, thin film deposition, etching and process integration for dielectric, silicon and compound semiconductor materials. The course also covers microphotonic integrated circuits and applications in telecom/datacom systems. Course assignments include four design projects that emphasize materials, devices and systems applications.

Students are introduced to the (hypothetical) task of developing an invisible (non-intrusive) security system to protect the school's treasured mummified troll! Solving the challenge depends on an understanding of the properties of light. After being introduced to the challenge question, students generate ideas and consider the knowledge required find solutions. They watch a portion of the "Mythbuster's Crimes and Myth-Demeanors" episode ($20), which helps direct their research and learning toward solving the challenge. They begin to study laser applications in security systems, coming to realize the role of lasers in today's society.

Principles of thermal radiation and their application to engineering heat and photon transfer problems. Quantum and classical models of radiative properties of materials, electromagnetic wave theory for thermal radiation, radiative transfer in absorbing, emitting, and scattering media, and coherent laser radiation. Applications cover laser-material interactions, imaging, infrared instrumentation, global warming, semiconductor manufacturing, combustion, furnaces, and high temperature processing.

Students apply everything they have learned about light properties and laser technologies to designing, constructing and presenting laser-based security systems that protect the school's mummified troll. In the associated activity, students "test their mettle" by constructing their security system using a PVC pipe frame, lasers and mirrors. In the lesson, students "go public" by creating informational presentations that explain their systems, and serve as embedded assessment, testing each student's understanding of light properties.