This B.Sc. degree combined two main subjects - physics and chemistry - which were studied over the course of three years. The degree consisted of lectures, laboratory classes and tutorials in all of the main areas of physics (eg, nuclear, electronics, theoretical, etc.) and chemistry (eg, physical, organic, analytical, inorganic, etc.).

For the first two years, a choice of subsidiary subjects, outside the scope of the two main subjects, were also studied (and examined) in blocks of either six months or one year duration each. The subjects chosen consisted of five blocks of mathematics (compulsory for physicists), the first two of which were covered as a single block over a short period of weeks, followed by three, more-demanding blocks which were well above GCE ‘A’ level standard. Other subsidiary subjects studied were biology, computing, and statistics.

A one year computer programming course in Pascal was compulsory for the first year of the degree. This consisted of a project to write a statistical program to analyse a sample of data. I received the highest grade during this course for writing a program which was unique in its ability to analyse data which was either (i) entered via the keyboard, or (ii) read from a pre-constructed data file.

Also compulsory for the first two years of the degree was a course entitled ‘Science, Technology, and Society,’ in which the philosophy of science, and its role in society were investigated. As part of this subject, it was necessary to give two presentations per year, on a relevant subject, to the remainder of the group.

The final year of the degree included a project, leading to the writing of a dissertation. The chosen project title, ‘The Design of an Experiment Suitable for Second Year Undergraduates Using Optoelectronic Components,’ resulted in an experiment entitled, ‘Experiment to Determine the Relative Spectral Sensitivity of Various Photoelectric Cells.’ This investigated the response of a range of optoelectronic components in relation to monochromatic light of uniform energy, at various wavelengths. See project note.

This degree, which combines the study of more than one subject, has proved invaluable in more recent work, providing the experience and ability to work and communicate across the traditional borders of single subject science.

Note on Undergraduate project, and spectral sensitivity.

Optoelectronic components are semi-conductor-based photocells dependent on photoelectric effects, ie: photoconductive devices; photovoltaic devices; and photoemissive devices. Examples include photoresistors, solar cells, phototransisters or photodiodes, etc. Such devices do not respond equally to all wavelengths of light, and are typically only sensitive to a small band of the visible, IR, or UV regions of the spectrum.

The photosensitivity of an optoelectronic device is defined as the way in which the property of the device (ie, photoconduction in a photoconductor, or, voltage produced in a photovoltaic device) varies with the wavelength of the light incident upon the device, for equal quantities of incident energy.

To measure photosensitivity, it is necessary to have monochromatic light over the range of wavelengths to which the photocell is sensitive. Rather than use individual monochromatic lamps, such as sodium lamps, etc., it is easiest to use a source of white light together with a monochromating device.

A difficulty arises, however, since the definition of photosensitivity requires that the incident light upon the photocell at each wavelength must be of equal quantities of energy. No single white light source produces such an output, and the spectral distribution of white light from a bulb may be greater in some wavelength regions than in others. (In using such a bulb, the output intensity would dominate the magnitude of the voltages, etc., being measured.) Also, dispersion effects due to the monochromator may affect the energy content of the light as is passes from bulb to photocell. It is therefore necessary to measure the energy output (spectral irradiance) of the source bulb used (using a radiometer), to prepare a calibration graph from which the results can be normalised. Then:

$$

                          RSS = p.d. - p.d.(Dark)
                                   I.E.(l)

where:
	RSS	=	Relative Spectral Sensitivity;
	p.d.	=	potential difference across the device or its load at wavelength l;
	p.d.(Dark)	=	potential difference across the device with no light incident on the photocell;
	I.E.(l)	=	incident energy at wavelength l.

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