​Compound Light Microscope

• ​The microscope used in our syllabus is called the compound light microscope.

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• ​It's named compound because it uses two types of lenses to magnify objects, which are the ocular & objective lenses.

​Parts of a compound microscope:

• ​The backbone of the microscope

• ​This is where you should hold the microscope with one hand when transporting it.

• The other hand is used to support the base of the microscope.

​Arm

​Parts of a compound microscope:

• ​Placed on the eyepiece

• ​Can be adjusted sideways to fit the distance between eyes

• ​Normally has 10x magnification power

​Ocular lens

​Parts of a compound microscope:

• ​Attached to the nose piece.

• ​A set of 4 lenses with different magnification power.

• ​Each magnification power is colour-coded

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1. ​Scanning lens: 4x (red)

2. Low power lens: ​10x (yellow)

3. ​High power lens: 40x (blue)

4. ​Oil immersion lens: 100x (white)

​Objective lens

​Parts of a compound microscope:

• ​This is where the set of objective lenses are attached to.

• ​Rotate this part when you want to change the objective lens power

​Nose piece

​Parts of a compound microscope:

• Modifies the clarity of observed image​ by adjusting the height of the stage

• ​Should only be used with the scanning objective lens

​Coarse adjustment knob

​Parts of a compound microscope:

• ​Located within the coarse knob

• ​Used to obtain sharp and clear images of specimen

• ​Can be used with any objective lenses

​Fine adjustment knob

​Parts of a compound microscope:

• ​Specimen on a slide is placed on the stage for observation

• ​Stage clip is used to secure slides

• ​On the stage, slide can be adjusted horizontally or vertically using the stage adjustment knob

​Stage

​Parts of a compound microscope:

• ​Acts as the light source

• ​Brightness can adjusted using the adjustment scroll on the side of the microscope

Illumination

​Parts of a compound microscope:

• ​Placed underneath the stage, directly under the specimen

• ​It gathers the light wavelength coming from the illuminator and concentrates it

• ​It functions the same way as the iris in human's eyes

Condenser

Next: Parts of Microscopes Short Quizzes​

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Calculating actual magnification​

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​Actual magnification

Every observed image has been magnified to a degree - depending on the magnification power of the lenses used.

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Compound microscope has two sets of lenses, therefore both must be taken into account.

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​Actual magnification = ocular lens x objective lens

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​Example:

​A specimen observed using the 10x objective lens on a microscope with 10x ocular lens magnification would produce an image that is 100x larger.