The Key To Micro World!

How to Select a Suitable Microscope for Blood & Sperm Observation(Bright Field / Dark Field / Phase Contrast / Heating Stage / Digital Camera)

How to Select a Suitable Microscope for Blood & Sperm Observation

Bright Field / Dark Field / Phase Contrast / Heating Stage / Digital Camera

In our daily work, there are many customers asking for a suitable microscope for observation of blood or sperm cell. Usually it is easy to recommend a simple biological microscope with Bright Field view to meet most of the customer's need. But, some customers has higher level request or special purpose which need Dark Field, Phase Contrast, Heating Stage, or Digital Camera to help them get the best suitable model for work. Hereby, we would like to list and explain more in this article -- How to Select a Suitable Microscope for Blood & Sperm Observation.


Biological Microscopes (A1 Series)with the magnification range of 100x-400x are frequently used for normal blood prepared slide or live blood observation. It is powerful enough to enlarge blood cell and magnify tiny structures or details of different blood cells.

However, blood could be observed in different ways. Some clients may only want to observe the movement and the shape of blood cells, while some other clients request to view the blood & sperm's activity to examine its quality. Sometimes measurement of the blood cell density, or count the cell's number would also involve in the observation work. And fine observation of blood cells might also be needed in the laboratory, such as observing the inner and outer structure of blood cells, that may request dark field view or phase contrast view rather than bright field view.


Different level biological microscopes & function accessories in Opto-Edu product range will be recommended in the following paragraphs according to specific requirements of blood observation. The 4 main categories of environments in which blood observation is frequently used are summarized, and recommended product link has been listed, enable a quick & easy view for each microscope from Opto-Edu.


Student School Level Biology Microscope (A11 Series)

Blood observation on biological classes in primary or middle school, often only requires basic observation of blood cell – to see the movement and shape of different blood cells, by student’s operation. A beginner-level biological microscope would be enough for this purpose.

With wide field eyepiece 10x and three objectives 4x, 10x, 40, a beginner-level biological microscope, also named as Student Microscope (A11 Series), has a magnification range from 100x to 400x. This magnification range is sufficient for students to observe and distinguish different most of the objects on prepared slides including blood cells and their movements. By having LED light source and coaxial coarse & fine focusing knobs, it is convenient for students to adjust focus from either left or right side of the microscope.


Student biological microscopes are usually with monocular head, which means it only has one eyepiece for eye veiw. Of course, it can be equipped with a USB2.0 digital eyepiece or LCD digital eyepiece like below (A59 Series), which enables many students to look at a specimen at the same time, it is a very nice way for teaching.

Or you can choose the all-in-one biological microscope (A33 Series) with built-in LCD & digital camera, like below models, to get easy & quick operation. Here are some typical & popular models for your choice.

Heating Stage Microscope for Animal Husbandry & Livestock Breeding

Because blood inspection in the breeding industry aims to examine the quality of live blood or sperm, the Heating Stage Microscope is always a standard outfit of our biological microscope recommendation.

A33.5100 has a heating stage and temperature control & display screen, by which you can set the temperature of the working stage from 30°C to 50°C, to keep blood or sperm’s live activity.


The heating stage could control and maintain the temperature of blood samples. By having it, blood cells could remain active and in a liquid state after it leaves the blood vessel. Benefit from the function of the heating stage, we could use biological microscopes to inspect the quality of live blood samples. Besides, biological microscopes with a heating stage are also a good choice for sperm inspection.


Besides A33.5101, we also have several other heating stage models for customer’s choice, as below:

Middle Level Microscope for Hospital Inspection

Middle-level biological microscopes are recommended in this category. With wide field eyepiece WF10x, 16x, 20x, achromatic objectives 4x, 10x, 40x, 100x, the magnification will reach up to 100x ~2000x. The classic 107bn series (A11.1007) biological microscope is the most popular model in this level, you can see them in many hospitals or even in some laboratory. It can supply high and stable quality image, to support qualitative examination of blood in hospital.

The middle level microscopes have bigger frame and larger working stage, which has more space to install some optional accessories, to upgrade the microscope with function like dark field, polarizing, phase contrast. Among them, the dark field and phase contrast function are quite useful to enforce the way to observe of blood & sperm.


Of course, you can choose a digital LCD camera to use with middle level microscope, which not only support sharing view to many people in same time, also support to connect to large HDMI monitor or USB computer. Control by mouse, it can take picture, video, or even can measure the size & square of blood cell.


Laboratory Level Microscope for Advance Research

For scientist or researcher, the laboratory level microscope (A12 Series) with infinity optical system, large working stage with dual slide holder, high brightness illumination is the idea tool for research. It is easy to get high quality image under Bright Field view for most of the specimens, including the blood and sperm samples. Furthermore, these models have full range optional function accessory. It can upgrade to Dark Field, Polarizing, Phase Contrast, and Fluorescent Function, which will enable the user to get clear image for transparent or low contrast specimens. It can work with different digital camera and LCD screen (A59 series), to capture image or video, measure size or square, and share the excellent micro world easily.


For blood inspection, the Dark Field Microscope and Phase Contrast Microscope is most useful functions often been used.

Dark Field

Compare with Bright Field, Dark Field presents a more distinct edge of blood cells. The principle of dark field is having an opaque disc placed underneath the condenser lens. The majority of lights are blocked by the disk, leaving only some scattered light reaching the slide. Those scattered lights are then reflected by blood cells, leading to a shiny peripheral around each cell.

Further, dark field largely increases the resolution. Dark field microscopes could distinguish particles at a resolution of 0.004um, which increased by 10 times than bright field microscopes. Thus, small particles and details are clearly presented under dark field.


You can choose a laboratory microscope , then add dark field condenser to get dark field view


And for customers easy choose, we also make some special Dark Field Microscope models (A10 Series), which has selected dark field accessories already, like:

See samples picture take by our customer using A12.2603-T + Dark Field Condenser to check the blood cell under Dark Field View. To make the cell image more bright and clear, our customer has made a special light source combine into the condenser which supplied extra light in the view field.


Phase Contrast

By utilizing interference phenomenon to make previously invisible amplitude shifts visible, phase contrast enables observers to see inner structure and rich details of those cells that are inconspicuous or transparent in bright field. This method enhances the contrast, making transparent inner structure of cells visible while increasing the contrast between previously visible cells.


Presented in this figure is a comparison of human glial brain tissue imaged in both Bright Field and Phase Contrast illumination. In Bright Field illumination, the cells appear semi-transparent with only highly refractive regions, such as the membrane, nucleus, and unattached cells (rounded or spherical), being visible. When observed using phase contrast optical accessories, the same field of view reveals significantly more structural detail. Cellular attachments become discernable, as does much of the internal structure. In addition, the contrast range is dramatically improved.


By adding phase contrast accessories, the laboratory microscope like A12.2603-T can clearly observe the flagella of blood or fine structure, it bring an extra view angle to find more details of the cells. Phase contrast microscope takes advantage of minute refractive index differences within cellular components and between unstained cells and their surrounding aqueous medium to produce contrast in these and similar transparent specimens.


P.S. How to make live blood slide & check the blood type:


P.S. How to Use Blood & Sperm Counting Chambers

Accompanied by blood counting chambers (E35.3503), or sperm counting chambers (E35.3520-A), the biological microscope could also support simple quantitative examination of blood samples.


Ensure that the special coverslip provided with the counting chamber (thicker than standard coverslips and with a certified flatness) is properly positioned on the surface of the counting chamber. When the two glass surfaces are in proper contact Newton's rings can be observed. If so, the cell suspension is applied to the edge of the coverslip to be sucked into the void by capillary action which completely fills the chamber with the sample. Looking at the chamber through a microscope, the number of cells in the chamber can be determined by counting. Different kinds of cells can be counted separately as long as they are visually distinguishable. The number of cells in the chamber is used to calculate the concentration or density of the cells in the mixture the sample comes from. It is the number of cells in the chamber divided by the chamber's volume (the chamber's volume is known from the start), taking account of any dilutions and counting shortcuts.


Scan the QR code Close
qr code


Empty List


Empty List