How to work

with Olympus

and Leica

microscopes

In the laboratory of medical microbiology you will work with:

• Microscopes Olympus CX-31 that are quite new and quite expensive

• Microscopes Leica that are even newer and also expensive

• There are two microscopes on each working table. Do not work with demonstration microscopes (next to the whiteboard and at the working table) without being told by your teacher!

• It is important not to dammage any of them (neither the white ones, nor the black ones)

• In following slides, Olympus microscopes are described. The work with Leica microscopes is very simillar, only some details may be different

Olympus microscopeOcularObjectivesMicroscopic tableCondensor irisPosition regulatorCollector irisLight regulatorMicroscrew and macroscrew

Swith on/off

Parts of microscope Olympus – 1:

Macroscrew

Microscrew

Parts of microscope Olympus – 1:

• Macroscrew: never use it when looking in the microscope! Only work with it when checking from the side that the obejective has a safe distance from your praparate

• Microscrew: even the microscrew may me only used at checking the position from side, when objectiv is drawn down (). At drawing the objectiv up () it is possilble to look to the ocular.

Parts of microscope Olympus – 2:

Oculars

On-off switch

Light regulator

Parts of microscope Olympus – 2:

• Oculars do not need your care, do not try to clean them or to regulate them by any way. They are 10× magnifying.

• On-off switch: allways switch off your microscope after finishing work with it!

• Light regulator: usually you do not need to use it (rather use collector and condensor iris, see below)

Parts of microscope Olympus – 3:

Condensor iris

Collector iris

Parts of microscope Olympus – 3:

• Collector iris, condensor iris (shutter): the more power of the objective, the more light you need. Both irises should be used together to regulate the light. To the right – less light, to the left – more light. In condensor iris, it is also possible to set it so that the number on it corresponds to the number on the objective. (In Leica microscopes, there is even the magnification of the corresponding objective written on the iris)

More light

Less light

Parts of microscope Olympus – 4:

Revolver changing of objectives

Condensor reagulation

Position regulator

Parts of microscope Olympus – 4:

• Condensor reagulation: do not use it at any circumstances!

• Position regulator is to „travel“ through your preparation

• Revolver changing of objectives:– Use 100× magnifying immersion obejctive

when observing stained preparations (Gram staining, Giemsa staining, Trichrom staining) and using immersion oil

– Use 4×, 10× or 40× magnifying non-immersion objectives when obesrving wet mounts (including results of Faust and Kato method in parasitology. No immersion oil is used when using these objectives!

Immersion oil use

•NEVER USE IMMERSION OIL WITH NON IMMERSION OBJECTIVES!!!

• When using immersion oil with immersion objective, it is necessary to clean the objective after use

Cleaning the microscope

• After use of microscope, non-immersion objectives should be only cleaned when dirty. Immersion obectives should be allways cleaned by benzine („BENZÍN“) and soft gause. Do not use filtration paper squares for cleaning objectives! It should be only used for cleaning of microscopical table (= the flat part of the microscope, where your preparation is placed)

Discarding/cleaning the preparations

• Preparations made by yourselves should be discarded after use to the disinfectant solution

• Preparations already prepared at the start of the practical should be cleaned (see further) and placed back to the original Petri dish

How to clean a preparation without destroying it• Clean the preparation using „BENZÍN“

and filtration paper square from the underneath (bottom) side thoroughly

• From upper side, do the same ONLY in areas where you see no visible preparation

• Never try to clean the preparation part of your slide. It is only possible to blot out excession of immersion oil using filtration paper (without moving the paper againts the slide!)

What to do after work with microscopes

• Switch your microscope off• Clean the objective(s), if necessary• Clean the microscopical table, if

necessary• Cover the microscope by dust jacket• Discard/clean yor preparation as

described

Main microscopical methods in medical microbiology

Drying and fixation

Coverslip Imersion system

Wet mount

no yes no

Stained preparations

yes no yesYou will learn the drying and fixation methods and all other techniques concerning preparing your preparation in first to practical sessions.

Self-check that you understood properly• There is a e-questionaire on

„ROPOT“ part of IS MUNI. Fill it, please. Succesfull filling it is a condition for your work in the first practical session.

We look forward to see you on the first practical sessions!

Your teachers