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A formatted Microsoft Word version of this paper is available for download here.
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Advanced Holography in High School Pearl V. John Department of Laser Technology, Columbia Area Career Center, Columbia, Missouri ABSTRACT Teaching advanced holography to secondary students is tremendously rewarding, and at the same time presents many challenges. In this paper, we describe our experiences teaching an advanced holography course as part of the Photonics Program at the Columbia Area Career Center in Columbia, Missouri. We also discuss how training in holography – using both simple and advanced techniques and equipment – prepares students for a variety of vocations involving laser technology. Keywords: Holography, secondary education, photonics industry training, vocational education 1. INTRODUCTION The following paper describes the use of holography in the Photonics Program at the Columbia Area Career Center. (According to the Center for Occupational Research and Development (CORD) Photonics is defined as "the generation, manipulation, transport, detection and use of light information and energy whose quantum unit is the photon"1). We will outline the benefits and the problems of teaching both simple and advanced holography within a High School teaching curriculum. Some of these challenges include; time and equipment limitations, equipment handling and classroom management issues. The benefits, which we believe far outweigh the problems, include; safety training, improvements in student motivation, understanding of light and wave theory, optics and equipment handling, communication skills, research skills, analysis of data and recording skills, problem solving and team-work skills. All of these skills are considered essential to the Photonics industry. Teaching Holography provides a foundation to teach these skills. 2. THE PURPOSE OF TEACHING HOLOGRAPHY AT HIGH SCHOOL 2.1. The Photonics Industry and Education The Columbia Area Career Center is a vocational technical school, combining both a practical and academic approaches to job training and education for High School Students and adults. The Photonics Program at the Career Center grew out of a customized training course developed for a local manufacturing company who agreed to pay for the cost of a new laser lab. This company began training Laser Electro-optical Technicians (LEOTs) at the Career Center in 1995 and aroused the interest of the High School students studying at the Center. The High School Program began a year later. CORD describes the Photonics Industry as including the following areas; Medicine, Communications, Defense/Public Safety/Aerospace, Environmental/Energy/Transportation, Manufacturing with Photonics/Test and Analysis and Computers (Entertainment, Consumer Devices, Hard Copy)2. The Career Center’s Photonics program teaches three years of laser technology to students starting in their 10th grade at 15 years with these Photonics Industry Areas in mind. Our first course, an "Introduction to Laser Technology" is a year long, practical arts class, introducing students to laser applications and some of the skills needed by a LEOT. For those students who wish to continue in the field we offer Photonics I and II courses to 11th and 12th graders. The Program was set-up to help solve a national shortage of skilled labor for the Photonics industry. This shortage is described by Neal Miller who instigated the Columbia Area Career Center Photonics curriculum, in his article "Public Education and Photonics"3. Miller states that; "Even if every college and technical school with an existing laser program filled all their classes each year it still would take nearly 200 years to fill the needs which industry will create by the year 2003. Presently, post-secondary institutions provide less than 1% of the actual demand for laser electro-optical technicians." With this national skill shortage in mind, our program was developed to introduce students to the knowledge and skills that are required by technicians in the Photonics Industry in order to speed up the education of a future workforce. 2.2. Holography Applications The ability to make a hologram is seen as a necessary skill for a Photonics Technician. Holography is of course an important discipline in the following areas; medicine, non-destructive testing, research and development, marketing, advertising, art and entertainment – to name a few. The National Photonics Skills Standard for Technicians, developed by CORD, the Center for Occupational Research and Development, outlined a list of skills and knowledge that Photonics Technicians required - as a result of the Goals 2000: Educate America initiative, which encouraged volunteer reports by certain industries. Number 59 of the Skills standards states that the following knowledge is required - 59: Interference, Principles of Holography, Setup and operation of holographic recording system, Demonstration of holographic reconstruction. Holographic recording materials.4 These skill standards are expected to be reached at the end of a two year Associates Degree Program. By teaching advanced Holography to High School students we aim to get them onto a fast track for college. We are currently working with several colleges to set up articulation agreements that may give our students college credit in High School. We also give them an advantage at college compared to other students who will not have their experience. Holography provides a foundation for teaching many Photonics skills in our Program and is also used as a ‘hook’ in our courses to inspire and encourage students to further their knowledge and skills. Andrea Robertson in her SPIE paper entitled, "Is there a need for Holography within Education?"4 Points out that; "As good educators we try to motivate students to learn by creating interesting and stimulating projects. Holography achieves these goals as most people in our society find 3 dimensional images mysteriously captivating…students want to make a hologram. To achieve this they are prepared to work and this time it is not for the teacher or for a grade but for their own personal satisfaction." Students are best motivated to learn when they are given tasks to accomplish that appeal to them. Holography does just that. Our curriculum covers light and wave theory – including; the electromagnetic spectrum, reflection, refraction, polarization, interference and diffraction – in order to teach these concepts to 10th graders we have to motivate the students into wanting to learn, by sparking their imaginations. Holography allows us to do this. Students are prepared to work hard to get their holograms made. Once they have a hologram students are then much more willing to learn the concepts behind the discipline. While holography provides an excellent teaching tool, there are many practical problems inherent in using the medium that have to be overcome. 3. THE CHALLENGES 3.1. Time and Equipment limitations. The biggest challenges to teaching holography in High School are time and equipment limitations. Our Introduction to Laser Technology course lasts for an hour and a half every other day and has four sections. Each class has a maximum of 16 students. We also have a daily class that meets for an hour and a half and runs for one semester. In order to make holograms in an hour and a half we organize our students into groups of four, and for the single-beam reflection holograms we may be able to get two holograms shot per-table if everyone works hard. Our first holography project of the year consists of making holograms in sand tables. The lasers sit in the sand and optics and objects are glued onto pipes with a very simple set up. The problems occur mainly when we try more advanced holography toward the end of the course. This year we tried making shadowgrams, with varying degrees of success. Each group of students is required to set-up the equipment themselves, solving the challenges of beam leveling and alignment, optics handling, the use of a variable beam splitter, taking beam path measurements, adjusting beam ratios, measuring beam power, and all of the other factors involved in advanced holography. These factors are extremely difficult for 10th grade students to master in ten lessons. The Career Center is extremely well equipped; we currently have six small engineering tables with air and one larger 8’ x 10’ engineering air table, a ruby pulse laser, argon and carbon dioxide lasers and numerous Helium Neon lasers. We also have positioning equipment, magnetic bases and a good supply of optics. The difficulties with equipment during the holography units are due to the number of students we have working; with five classes (70 students) we have to leave our set-ups on our engineering tables once each group has built a camera. Each group of students complained that the previous group had ruined their set-up and that they needed to re-build their cameras. Students found it very difficult to adapt cameras and be flexible. This was understandable. The ideal situation for a holographer is to work on their own, or with an assistant, without such limiting time restraints or the need to share equipment in the middle of a project. Our Photonics I and II courses with about 10 students in each, also run congruently, in the same lab areas this year. This meant that, on occasion, we had 52 students wanting to use the same equipment. This understandably led to classroom management problems at times, and was a result of timetabling conflicts. This was the first year that the Photonics II course was offered, so naturally we encountered some problems. 3.2. Breakage Another problem we encountered with our holography equipment was breakage, mostly by the 10th Grade "Introduction to Laser Technology" students. Any piece of equipment which passes through fifty hands daily has to be extremely hardy, and people aged 15-17 years can be clumsier than adults – especially when under the pressure of handling new equipment and learning a new skill. We have observed the following problems with equipment: much of it has been dropped or mishandled; for example optics, including beam splitters, mirrors and glass have been regularly dropped, chipped and handled incorrectly - leaving finger prints and dirt residue. Power supplies and light meters have been knocked off tables and equipment has also been damaged through negligence - magnetic bases have been damaged by being turned on and hauled off the tables (as a test of strength) which has also scratched the engineering tables. Items have also been lost, making positioning equipment unusable; in particular the small silver ball bearings found in dual ring laser mounts, mirror and lens mounts. Spray adhesive has on occasion been used to glue equipment to tables rather than hot-glue by mistake. It can be argued that much of this damage can be attributable to the maturity level of the age group we are teaching. Many of these problems do not occur with the Photonics I and II courses for the older students. Learning to handle optics correctly and demonstrate respect for equipment are skills that we aim to teach on our course. These lessons could, however, prove very costly to the department over a matter of time. 3.3. Classroom Management Part of the problem of equipment mishandling can also be considered a classroom management issue. The care and maintenance of our equipment will be top priority for the next academic year. We need to instill in the students a sense of ownership for the equipment, by ensuring the return of the equipment to its correct storage area. Students are currently awarded daily grade points for leaving their work area tidy, however this reward has not solved the problem of equipment left lying around the classroom at the end of the lesson. Other classroom management issues occur during holography instruction. Discipline problems arise because of team conflicts. These are mainly due to communication problems between team members and a lack of understanding of the task in hand. Students can become easily discouraged when they don’t understand and some will start to act inappropriately. When working in the dark, under safe lights, there are many opportunities for a frustrated student to misbehave. Advanced holography is perhaps the hardest unit on our course and not all students will master the skills necessary to make a split beam hologram in the time allowed and under the classroom conditions described above. Another factor that the instructors have observed is the make-up of our classes, which tend to have only a small number of female students in them; the classes which are mostly boys tend to be the most challenging to manage. A more even balance of numbers of girls to boys tends to result in a higher display of maturity in the classroom. We are attempting to encourage as many non-traditional students into the class as possible for many different reasons. Despite the difficulties with time, equipment (and financial) restrictions, breakage and classroom management outlined above, the benefits of teaching advanced holography, far outweigh the challenges. 4. THE BENEFITS OF TEACHING HOLOGRAPHY 4.1. Holography inspires and motivates students As outlined in the introduction to this paper, one of the most important benefits of teaching advanced holography to students is increased student motivation. Students on the "Introduction to Laser Technology" course appreciate the creative freedom of being able to choose their own holographic subject matter. Students are encouraged to bring in personal, valuable objects – objects that have a story attached for their first hologram. Talking about their subject matter helps build a sense of community in the classroom. The last holography project involved students bringing in photographs of family or friends to use as a subject for shadowgrams. This personal approach strengthens the understanding that students are learning for themselves – learning is not being imposed upon them. It helps to break down the barriers between school and home-life. The Photonics I & II courses allow a much greater degree of freedom to pursue holographic projects, due to the structure of the course and class sizes. Students are given one day a week to work on their own research projects and class sizes are smaller. Photonics students also have the opportunity of working with more powerful lasers and professional grade equipment This element of the curriculum has proved most successful; this year two of our Photonics II students submitted research papers to the SPIE annual conference and one was accepted. Mike Walk, will be giving his paper on Strain/Displacement via interferometry – testing a carabina. Mike has used holographic interferometry to non-destructively test climbing equipment to gauge when the equipment needs to be retired. Mike is a climber and wishes to provide a low cost service to voluntary organizations to test aging equipment. His project consisted of making numerous double exposure, single beam reflection holograms of the climbing equipment under different amounts of pressure to simulate different loads of weight. Other student projects have included the design of a beam path enclosure to make high-powered lasers suitable for use in the classroom and other safety devices, shutters for lasers to use with holography, and the production of cylindrical and animated holograms. Last year two students helped in the writing of an educational web site, with the aim of publishing their research projects on colour holography experiments. Students have also opted to try to build lasers and research light theory. Students have had to write an abstract for their research project for approval by their instructor, develop a product and write a paper that they present to their instructor and classmates at the end of the project. The freedom to do a research project fires student’s enthusiasm. Another of the benefits of developing a research project in High School is that students will receive support and tuition with no extra cost if their project becomes marketable. This is in contrast to many colleges, which will help patent inventions, but may take up to 90% of the financial rewards. 4.2. Learning Laser Safety Skills Making a hologram is the second unit on our "Introduction to Laser Technology" curriculum and Laser Safety is the first. In order to make a hologram, students have to pass a safety test and achieve 100%. The promise of making a hologram provides the motivation for students to study for their tests and rarely are any students held back because of failure. Holography again provides a strong motivation for learning. The more advanced the holography, the more powerful laser is needed and the greater the need for safe practices and safety expertise. During their first holography unit students learn the role of a Laser Safety Officer (LSO), each taking turns as an LSO assistant. They are tested on the Laser Institute of America’s (LIA) safety rules6 standard operating procedures for the use of lasers and performance tested on the correct use of safety equipment. Our safety equipment includes; laser shutters, eye wear, laser safety danger and caution signs, beam terminators, beam shrouds, index cards for checking position of the beam and correct clothing. Students are also required to know the LIA’s Laser Classifications and identify different classes of laser in order to recommend appropriate safety precautions. In order to make safety more fun, we have instigated periodic safety competitions, with holographic pencils given out for prizes. This lighthearted approach makes it much easier for students to point out their peers’ mistakes and safety infractions. They are much more likely to bring problems to the instructor’s attention if it is going to exclude their friends from the chance of winning a prize, rather than getting them into trouble. Students become more able to monitor their own behaviour, rather than relying on the instructor. The Photonics students, who act as safety role models and help teach Introduction to Technology students Safety, are rewarded by being allowed to use more powerful lasers than the younger students. The demonstration of good safety practice is extremely important at the High School level to instill a respect for lasers that are currently being sold cheaply in shops as if they were a toy. Laser pointers are now banned in many school districts because of children aiming them at the police, pilots and bus-drivers. In Columbia last year a 28-year-old had to have his eyeball removed as a result of staring down a class IIIa laser pointer for a minute and a half. The students are amazed to learn that the lasers they use to make holograms can be less powerful than a laser pointer and that the LIA recommends the use of laser safety glasses with a IIIa laser. Students use two different types of holography material on the course and as such deal with two different chemical developing procedures. They are taught correct procedure for the handling and mixing of the chemicals necessary to develop their holograms. Students use safety glasses and gloves while developing and are taught the relevance of material safety data sheets and emergency first aid in the darkroom. Photonics Students also undertake a CPR training course. Local business safety experts, parents, students and teachers meet regularly in a safety committee to discuss safety issues and to monitor the development of safe working practices in the classroom, which will hopefully last a lifetime. 4.3. Classroom Management While it has been observed that advanced holography can cause classroom management problems, there are also benefits to discipline in the lab area.. Students have to behave appropriately in order to be able to make a hologram. They have to be prepared to turn overhead lights on and off at correct times and during settling times and plate exposures they have to remain completely quiet – which is difficult for 15 year olds especially. Students have to show respect for each other’s work and not talk or move during another student’s exposure. They have to learn to follow directions in order to get the best results. Failure to follow those instructions often means failed result. The results are tangible. 4.4. A Tool for teaching light theory One of the Photonics Programs goals is for students to explain how holography works in depth. After making a hologram, students learn the following; light theory – wave and particle, the electromagnetic spectrum, reflection, refraction, polarization, diffraction and interference. Holography provides the foundation for teaching these concepts. Each concept is taught with ‘hands on’ labs and once the concept is understood the instructor relates the subject back to holography, explaining how it is relevant to the way the students’ holograms worked. Holography is also a useful tool for teaching optics handling, the vocabulary of the Photonics industry, accurate measurement skills using, for example, protractors and light meters, the care and maintenance of equipment, dexterity skills in the building of holography cameras, co-operation and problem solving skills. 4.4. Problem Solving Skills 4.4.1. The importance of documentation All of our students are taught to follow a set procedure for maintaining a record of every experiment or lab that they do. They record a title, date, name and lab partners, an objective; they list equipment, procedure, data and analysis. Every student maintains a logbook throughout the Program and when shooting holograms they draw a diagram of their set-up, record their exposure times and power readings, writing a detailed description of their results and an analysis to explain why their hologram looked like it did. They trouble-shoot and record any problems encountered during the lesson, including teamwork problems. The logbook has been taken directly from the practices of a local laser manufacturing company which trains its staff to use these carefully kept records as problem solving tools. 4.4.2. Team work skills In order to produce a hologram, students have to work co-operatively. Due to the relatively large number of students in each class it is necessary for students to help one another, answering each other’s questions and teaching one another as it is not always possible for the instructor to answer everyone’s questions at once. Students are encouraged to solve problems within their teams, or at least recommend solutions when they ask for the instructor’s help. 4.5. Creative thinking The Introduction to Laser Technology tries to maintain a balance between Art & Science. Projects other than holography include; laser light sculpture, designing for laser manufacturing and laser light shows. During the advanced holography unit students are introduced to the field of contemporary art and the place of holography and lasers within the art industry. Students research artists using holography and are encouraged to contact the artists for further information. This helps the students’ communication skills and empowers students with regard to contacting those involved with Photonics for help or general information. Many of the students have no existing knowledge of contemporary art. They are introduced to the current concept of postmodernism and have a brief lecture on the concerns of artists working with holography. They are shown slides of Holographer’s work before being asked to do their own research. Not only have students not previously heard of postmodernism, but they also have no opportunity to see contemporary art. They have had no exposure to installation and they are also introduced to the concept of public art. Last year a small group of students and I took part in a local art fair, producing a chair covered with diffraction gratings and single-beam reflection holograms made during the year. We won an award for the piece, entitled ‘Light Chair’ that has given students more of an interest in the art world. 4.6. Holography raises the profile of the program Working with holography has given the student’s work and the Career Center a lot of good publicity. Students have been interviewed on holography educator Frank DeFreitas’ internet radioshow, ‘Holoworld.com’. This provided an enormous boost to the student’s confidence. Students were shown a number of times on local news channels and one project in particular, Saturday Science in conjunction with the University of Missouri, attracted a lot of local media attention and increased our student in-take for the next academic year considerably. One hundred 8th and 9th grade students were invited to come to the Career Center to make holograms and learn about occupations linked to the Photonics Industry, half of the students were girls and a number of them signed up to take ‘Introduction to Laser Technology" as a result, increasing our current number of female students. Our existing students acted as holography instructors during the project. They were well paid during the project and the work helped boost their confidence and improve their communication skills. The benefits of teaching advanced holography in High School then are; increased student motivation, a tool to help solve classroom management problems, a vehicle to teach laser safety, light theory, contemporary art practice, and practical skills gained from the building of holography systems with professional equipment CONCLUSION Teaching advanced holography at High School gives students valuable skills required by the Photonics industry – team building and problem-solving, knowledge of light theory and laser applications, the ability to research and contact representatives from local industries and the gaining of self-esteem from achieving difficult practical tasks. Our first graduates are entering Associate Degree Photonics Programs at the post-secondary level and one has just obtained a position at a local laser manufacturing company as a LEOT. We believe at the Columbia Career Center that while the current Program needs continued assessment and improvement, the benefits far outweigh the problems in teaching the subject of advanced holography at the High School level. ACKNOWLEDGEMENTS Neal Miller – Previous Photonics Instructor, Corporate Trainer and Program Consultant. Rick Shanks – Photonics Instructor, Columbia Area Career Center. Mike Walk – Photonics II student, Columbia Area Career Center. Dr. T.Jeong, Professor Emeritus, Lake Forest College, Illinois. Program Consultant REFERENCES 1. Center for Occupational Research and Development, National Photonics Skills Standard for Technicians, p.4, 1995. 2. Center for Occupational Research and Development, National Photonics Skills Standard for Technicians, pp. 17 and 26, 1995. 3. N. Miller, Public Education and Photonics, Optics and Photonics News, Vol. 10 No. 2 pp. 49-50, 1999. 4. Center for Occupational Research and Development, National Photonics Skills Standard for Technicians, pp. 17 and 26, 1995. 5. A. E. Robertson, "Holography in Education: a Partnership between Science and Art," Fifth International Symposium on Display Holography. 2333, pp. 233-244. 6. Laser Institute of America, Laser Safety Guide, VI., Laser Institute of America, Orlando, 1993. Return to Holography Classes |
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