Last week in one of my classes a student with no vision asked why he needed to learn about how to use a microscope. The light microscope is one of the most important technologies developed for life science as it was essential in the discovery of the cell and microorganisms. Therefore all biology students should be taught the historical scientific significance of the microscope as they learn about how the microscope operates. In response to the question posed by my student, I explained the importance of the microscope and indicated that I would provide models or raised lines of images we view under the microscope. This student has turned out to be one of the most involved and interested as we have studied the manner in which the light microscope functions.
Which Microscope is Best for Students with Low Vision?
Though few students with visual impairments benefit from utilizing a light microscope directly, many students with low vision can benefit from devices which allow the microscope image to be displayed on a screen rather than through the eyepiece of the microscope. The Celestron USB microscope is one such device which I utilize regularly for biology. (http://www.celestron.com/browse-shop/microscopes) The specific microscope that I use in class is the Pentaview LCD Digital microscope. (http://www.celestron.com/browse-shop/microscopes/digital-microscopes/pentaview-lcd-digital-microscope). The microscope is equipped with a small screen but can be connected to a large monitor to allow for viewing by students with low vision.
How Can Microscope Work Be Made Accessible to Students Who Are Blind?
Students who are blind should be provided with models or raised-lines of the images displayed as low vision students view the image. Cell Zone (http://www.cellzone.org/) is a wonderful resource which provides 3-D models of some cell structures. This set is described in more detail in the resource section of the website. (http://www.perkinselearning.org/accessible-science/cell-zone)
If available, a 3-D printer is an excellent resource for producing models including models of plant, animal and bacterial cells, as well as viruses. Please see the following link describing the use of 3-D printers to produce viral models. http://www.nanowerk.com/news2/
The cell model that I recommend is the 3B® Animal and Plant Cell Models. They are available from Carolina Biology Supply (http://www.carolina.com/cell-models/3b-animal-cell-model/563957.pr?catId=&mCat=&sCat=&ssCat=&question=animal+cell+model) There are other good models available as well. The structures found within the cell (organelles) are often depicted as raised-line drawings in the textbook. Ideally, the TVI (teacher of the visually imparied) will provide 3-D models of the organelles as well. An artist may produce these if time allows. (Please see the blog section of the website Collaboration with an Artist to Create Scientific Models)
As middle school and high school life science students are introduced to the light microscope, students who are visually impaired should also be taught the parts of the microscope and their functions. This can be accomplished more effectively by allowing visually impaired students to explore the microscope tactually while the instructor is teaching. Ideally, the TVI will be present for this lesson. The TVI should review the parts of the microscope before the lesson. If possible, obtain an older microscope for the student to use so that the student does not accidentally damage the microscope.