Where to buy coverslips

High resolution (= High N.A.) microscope objectives are usually designed to be used with a 170 micron thick glass coverslip, which corresponds to grade No. 1.5. This is indicated on the lens as part of the lens marking,  “∞/0.17”, which can be translated as: infinity corrected optics, requiring a coverslip of 0.17mm (170µm). Microscope objectives perform poorly when imaging through thinner or thicker glass, or when imaging cells that are not on the surface of the coverslip (e.g. they have been grown or placed on the slide rather than the coverslip. Using the wrong thickness of coverslip introduces spherical aberration in the image, which results in dimmer fluorescence.

Thickness number

#0 corresponds to a range from 85 to 130 µm
#1 corresponds to a range from 130 to 160 µm
#1.5 corresponds to a range from 160 to 190 µm
#2 corresponds to a range from 190 to 230 µm
#3 corresponds to a range from 250 to 350 µm
#4 corresponds to a range from 430 to 640 µm

#1.5H corresponds to a range from 170 to 180 µm

Schott Glass makes the glass from which most coverslips are made.
For more information, visit: http://www.microscopyu.com/articles/formulas/formulascoverslipcorrection.html.

Here is where the CIC get their coverslips and the list of catalog numbers:

http://www.emsdiasum.com/microscopy/products/histology/coverglasses.aspx#72195

72230-01     12mm     #1½     (.16-.19 mm)     1 oz.

72230-10     12mm     #1½     (.16-.19 mm)     10 oz.

72222-01     18mm     #1½     (.16-.19 mm)     1 oz.

72222-10     18mm    #1½     (.16-.19 mm)      10 oz.

72224-01     22mm     #1½     (.16-.19 mm)     1 oz.

72224-10     22mm     #1½     (.16-.19 mm)     10 oz.

72225-01     25mm     #1½     (.16-.19 mm)     1 oz.

72225-10     25mm     #1½     (.16-.19 mm)     10 oz.