Operation and Calibration of Microscope

1.0 Objective
To lay down a procedure for Operation and calibration of Microscope.
2.0 Scope
This Standard Operating Procedure at Microbiology laboratory Quality control department of abc company,
3.0 Responsibility
3.1 Concerned Officer/Executive shall be responsible to follow this SOP.
3.2 Department Head or his/her designee shall be responsible to implement and ensuring to compliance of this SOP.
4.0 Abbreviations and Definitions
SOP : Standard Operating Procedure
QC : Quality Control
QA : Quality Assurance
SD : Standard deviation
Cal : Calibration
5.0 Procedure
5.1 Microscope is used for identification of Microscopic Characteristics of drug substance.
5.2 Make sure all the exposed optical surfaces are free of dirt. Plug the power cord into grounded outlet

(ensure that power supply plug is properly grounded otherwise it may damage the power supply transformer.

Switch on supply and keep regulator in medium position.
5.3 Adjust the observation Head to convenient working position.
5.4 Rotate the nosepiece until the lowest power objectives, the greater the area of the speci men surface included

in the field of view. Lower power objectives also have a much greater depth if focus and use fir initial focusing

and viewing.
5.5 Take down the stage surface to a fairly low position with the help of coarse focus knob.
5.6 Make sure that the stage surface is free of dust, grit or any other material that will interfere with the

movement of the specimen slide across the surface of the stage or scratch the stage. Position the specimen area

of the slide (cover glass up –wards) over the center of the stage aperture use the stage control knob to move the

specimen slide to the desired position.
5.7 Looking through the Binocular Head, raise the stage by adjusting the coarse focus knob until an image

appears-thereafter.
5.8 Adjust with the help of fine focus knobs to sharpen the image.
5.9 Look at the image and adjust the condenser aperture to obtain the best possible resolution. The clarity

of the image depends upon the size of the aperture. As the aperture becomes smaller. As aperture becomes

smaller, the contras and the depth of focus increases. The clearest image is produced by combination of these factors.
5.10 Examine the specimen. When you find a feature you wish to observe at a higher magnification, move

the slide so that the feature gets centered in the field of view.
5.11 Until you gain sufficient experience in use of this microscope, it is wise to always obtain an image with lowest power objectives and then going to successively higher power objectives one step at a time.
5.12 When using objectives of higher numerical aperture proper focusing of the abbe condenser is important.

Move the abbe condenser by racking the condenser movement knob, up down so that the field is evenly illuminated.
5.13 This microscope has a rotating potentiometer for regulating the light intensity. Rotate the potentiometer

knob from low to high as you go from low magnification to high magnification objectives for obtaining best

light in the field of view.
5.14 The procedure for the examine a specimen using the oil immersion objectives is as follow:
5.15 Rotate the nosepiece so the low power objective (10X) is in the light path.
5.16 Place the one-drop of immersion oil on the lighted area of the specimen slide.
5.17 Rotate the nosepiece so the low power objective100X oil immersion objectives are in the light path.

Be cautious than 40X objective should not get in contact with oil.
5.18 Since all the objectives are Para focal, the specimen shall be visible when changed to 100X.

Use fine Focus knob to get the best image.
5.19 After each session when you finish using the oil immersion objectives, wipe off the traces of oil

from the objective, and the specimen if it is with cover glass, with a lens issue or clean soft cloth moist with

lens cleaning solution.
5.20 Calibration
5.20.1 Calibration shall be performed for accuracy of microns with calibrated micrometer by authorized

out source calibration party once a six months and when ever a major maintenance is done.
5.21 General
5.21.1 Record the every usage in form as given in Annexure-1.
5.21.2 Document the calibration record is provided by out source calibration party.
6.0 Forms and Records
6.1 Usage log – Annexure-1
7.0 Distribution
7.1 Master copy – Documentation Cell (Quality Assurance)
7.2 Control copy – Quality Control
8.0 History