Appartus for Young's double slit? I am wanting a full description of an apparatus used for Young's double slit (not necessarily the one that Young himself used though), which takes monochromatic light (though not laser light) and sends it through a series of slits and lenses to make it coherent and collimated (and maximising the end intensity) before finally reaching the double slit. Does anyone know any resources that will explain such a set up in detail?
Below I have included a diagram of the sort of set up I mean:

Although here I can explain what each component does some I am a bit unsure about and want a reliable recourse to confirm.
 A: The company TeachSpin builds a two-slit interference instrument for use in the advanced/modern physics lab.  There are several descriptions and schematics at that website.
They do not have a lens before or after the single slit. The single slit is physically close to the source.
I've used the instrument several times and it gives beautiful results for both the fine and coarse interference intensities. It also allows you to selectively block either of the two slits so that you can show that the two-slit pattern is not the sum of two one slit patterns.
A: Are you sure that the single slit between lenses 1 and 2 is a slit and not a pinhole? 
If I were setting this up without a laser, I would use a pinhole below the diffraction limited spotsize of the first lens at the focus: this gives you an aberration free spherical wave at the output of the pinhole (same idea as a point diffraction interferometer / wavefront sensor), which is then collimated by lens 2 and input to the two slits. Lens 3 simply matches the diffraction pattern to the screen available, particularly if you're trying to use a CCD chip. 
So in summary:


*

*Lens 1 boosts the power throughput by getting maximum power to the pinhole;

*Pinhole destroys wavefront phase information (by accepting only input in a smaller than diffraction limited region) thus outputting aberration free spherical wave;

*Lens 2 collimates

*Double slit: well that's the whole point of the experiment!

*Lens 3 matches diffraction pattern with imaging screen / CCD camera.

