Thursday, February 27, 2014

Human Esophagus Under the Microscope

The human esophagus is a muscular tube that connects the throat with the stomach. At about eight inches in length, it is lined with a moist tissue called mucosa. The esophagus' primary purpose is to pass food from the mouth to the stomach.

100x esophagus under microscope
Human Esophagus captured at 100x under a biological microscope.

esophagus under microscope 100x
Human esophagus, 100x, captured under a brightfield microscope.


These first two images of the human esophagus were captured using the Richter Optica U2 biological microscope and a 5mp CMOS microscope camera. Both were captured using brightfield with magnification at 100x and 400x.

Using an Epi-Fluorescence microscope, the following image was captured at 400x magnification. Notice that the human esophagus prepared slide is in the exact same position as the image captured above.

esophagus as seen with fluorescence microscopy 400x
Human Esophagus captured with epi-fluorescence microscope at 400x.
The human esophagus prepared slide can be purchased in the Histology: Human Organ prepared slide kit from Microscope World.

Tuesday, February 25, 2014

Kids Science: Dollar Bill Under the Microscope

A great kids microscope project involves using a stereo microscope at anywhere from 10x-40x magnification to view a single dollar bill. How many hidden items can you find on a dollar bill? Here are a few fun facts about the US Dollar.

If you place a dollar bill with a frayed edge under the stereo microscope at a higher magnification, you might be able to see the linen fibers of the bill. A dollar bill is made out of a blend of linen and cotton and this is why if you accidentally jump in the pool with money in your pocket, the dollars survive the washing. Look closely with the microscope - there are actually red and blue silk fibers woven throughout the bill.

On the face of the dollar bill you will see a large letter inside a circle and a number off to the side of this letter. The seal with the large letter tells you the Federal Reserve bank that placed the order for the dollar bill. A = Boston, B = New York City, C = Philadelphia, D = Cleveland, E = Richmond, VA, F = Atlanta, G = Chicago, H = St. Louis, I = Minneapolis, J = Kansas City, K = Dallas, and L = San Francisco.

The letter on the dollar bill tells which Federal Reserve Bank placed the order.
The number to the left of the large letter corresponds to that specific letter placement in the alphabet. For example, "F" is the 6th letter in the alphabet. The letter "D" has a 4 next to it.

What is hiding in the corner of this shield?
Take a look at the shield behind the 1 in the corner of the dollar bill. Can you see a small spider or an owl?

Find the Great Seal of the United States on the bill. Do you know that the founding fathers of America approved this design in 1782? Ben Franklin, John Adams and Thomas Jefferson all were involved in the design.

Find the words Annuit Coeptis. Do you know what this means? The first of three Latin phrases on the back of the dollar bill are translated "God has favored our undertakings."

The Great Seal of the United States
Under the pyramid do you see some Roman numerals? Look closely with your microscope. The letters MDCCLXXVI stand for 1776, the year the Declaration of Independence was signed. M = 1000, D = 500, CC = 200, L = 50, XX = 20, VI = 6. If you add them all together you get 1776.

What else can you find on the dollar bill when looking at it under the microscope? Whose signatures are on the bill? What items do you think were used to keep counterfeit money from being made?

Friday, February 21, 2014

How to Parfocal Microscope Objective Lenses

Microscope World has a full page dedicated information on how to parfocal microscope objective lenses here.

A parfocalled microscope objective lens means that on a biological microscope when you move up in magnification from one objective lens to the next the specimen remains in focus.

If you have a microscope objective lens that is not in focus when the other lenses are, you can adjust the lens by following these steps:

Remove the objective lens from the microscope.

Unscrew and remove the outer covering from the lens.

Once the cover is removed, you will notice a small screw that, when tightened or loosened, will adjust the distance between the tip of the lens and the threads on the top of the lens.

With the cover still removed, screw the objective lens back onto the microscope. Move down to the lower objective lens power and ensure that the objective is in focus when looking through the eyepieces. Move back to the lens that needs to be parfocalled. Rather than turning the focus knob to focus the lens, adjust the small screw on the side of the lens until the image is crisp and clear.

Remove the microscope objective from the microscope, replace the metal cover on the lens and screw the lens back into place on the microscope. Learn more about how to parfocal microscope objective lenses here.

Wednesday, February 19, 2014

Physician Laboratory Microscopes

Physicians use microscopes for dermatology, histology, hematology and microbiology. Depending on the application, phase contrast might be used. High quality optics are a prerequisite. A few common laboratory microscopes used by doctors include the Meiji MT5300 and the Motic BA310.

phase contrast microscope image
Motic BA410 microscope set up for phase contrast.
Microscope World has a specific physician microscope page on our website with the most commonly purchased laboratory physician microscopes.

Histology image captured with physician lab microscope.
If you are a lab or a doctor looking for a specific microscope setup, please contact Microscope World for a customized quote.

Monday, February 17, 2014

Moss Under the Microscope

Moss typically grow close together in shady, damp locations. Moss is a small, non-vascular plant that absorbs water and nutrients from its leaves, while sunlight is harvested to create food by photosynthesis. The moss images below were captured at 400x magnification using the Richter Optica U2 biological microscope.

Moss 400x image
Moss captured at 400x under the U2 biology microscope.

Moss under the microscope, 400x.

 Images were captured using a 5 megapixel microscope camera with software. The USB microscope camera provides a live image from the microscope onto the computer. The software can be used to add notes to images, make measurements and even capture video.

Moss under the microscope
Moss under microscope at 400x.

The moss prepared slide is part of the Botany Prepared Slide kit and can be purchased here.

moss at 400x under microscope
Moss captured at 400x under a brightfield biological microscope.

Friday, February 14, 2014

Happy Valentines Day!

Happy Valentines Day from all of us at Microscope World, including the Zebrafish!

Zebra fish image under the microscope on day 2
Zebrafish captured on Day 2 under a stereo microscope.

Wednesday, February 12, 2014

Mold Under the Microscope

Mold is a fungus that grows in multi-cellular (often tubular shaped) filaments resulting in discoloration and sometimes a fuzzy appearance on whatever it grows on. Molds cause biodegradation of natural materials. Mold also plays an important role in biotechnology and food science in the production of various foods, beverages, antibiotics and pharmaceutical products.

Mold captured at 100x magnification
100x magnification - mold captured under the U2 microscope.

There are thousands of kinds of mold. The ones shown here are Aspergillus. This specific prepared slide is available to view under the microscope in the Botany Prepared Slide Kit.

Aspergillus, 400x, under microscope
400x magnification - mold captured under the U2 LCD digital microscope.


Images were captured using the Richter Optica U2 biological microscope with the DCM5.1 5mp microscope camera and the Richter Optica U2 LCD digital tablet camera microscope.

400x image of Aspergillus (mold) under microscope
400x magnification - Aspergillus (mold) under the microscope.

Monday, February 10, 2014

The Features of a Polarizing Microscope

Polarizing microscopes are used to view minerals, drugs, chemicals, rocks and geological particles. But what exactly makes a polarizing microscope different from a biological microscope?

polarizing microscope
Meiji Polarizing Microscope MT9200
polarizing microscope lenses
Polarizing microscope lens slots.
  • Below the eyepieces in the body of the polarizing microscope is the Bertrand Lens, which can be swung out or slid in and out of the axis tube. The Bertrand Lens is used to analyze the back focal plane of the objective.
polarizing microscope features
Polarizing Microscope Features
  • The analyzer rotates at least 90°.
  • The 1/4 Wave Plate or Quartz Wedge is used for analytical work. 
  • Compensator and Retardation Plates are included in many polarized light microscopes with a slot to allow the insertion of compensators and/or retardation plates in between the crossed polarizers. These are used to enhance optical path differences in the specimen.
  • Strain Free objectives and a strain free condenser are used, which contain anti-reflection on the glass parts. The strain-free design precludes the setting up of mechanical stresses in the glass elements by special glass selection and/or construction of lens mounts. The anti-reflection films enhance image contrast and reduce possible disturbing interference patterns at the glass-air interfaces.
  • The substage contains the condenser, iris diaphragm, carrier for a polarizer, and sometimes an additional carrier for a sensitive tint plate.
strain free microscope condenser
Polarizing microscope strain-free condenser.
  • The rotating stage is graduated in degrees. A vernier is included to permit reading of angles to the nearest tenth degree.
polarizing microscope stage
Polarizing microscope stage.
Polarized light microscopy is capable of providing information on absorption color and optical path boundaries between minerals of differing refractive indices. Contrast-enhancing techniques reveal detailed information concerning the structure and composition of materials that are very useful for identification and diagnostic purposes.

Friday, February 7, 2014

Gems under the Microscope

Gemologists typically use either a stereo microscope or a gemological microscope when viewing precious stones or gems. A gem clamp is used to hold the stone in place and often darkfield illumination is used to direct the light around the precious stone.

These gems were captured under a Richter Optica S6 LCD tablet camera stereo microscope using 7x magnification.

precious stone under microscope
Gem captured under a stereo microscope.
Gem under microscope image
Precious stone captured under stereo zoom microscope.

Tuesday, February 4, 2014

Microcope Sample Characterization by Light

Light behavior is revealed in different forms including reflection, refraction, dispersion, diffraction, interference, absorption, polarization and excitation. Each of these forms are described in detail below and provide a basis for understanding the various specimen characterization methods by light action with the microscope.

Reflection:

Reflection of light from a smooth surface (such as a mirror), takes place along a definite direction determined by the direction of the incident ray, and is called regular or specular reflection. Reflection from a rough or matte surface occurs in many directions and the incident beam is said to be "diffused" or "scattered". Non-luminous objects become visible by diffused reflection.

light reflection illustration
Light reflection from a smooth surface.

light reflection from a rough surface
Light reflection from a rough surface.

Refraction:

A ray of light of a single wavelength  undergoes an abrupt change of direction upon passing obliquely from one medium to another. The effects of refraction are responsible for a variety of familiar phenomena, such as the apparent bending of an object that is partially submerged in water and the mirages observed on a dry, sandy desert. The refraction of visible light is also an important characteristic of microscope lenses that enables them to focus a beam of light onto a single point.

light refraction
Light refraction


Dispersion:

The spreading out of light into its component colors is known as dispersion. For example, when a narrow slit is illuminated by white light which is then passed through a prism, refraction takes place and the constituent colors are spread out into an array called a spectrum.

ligh dispersion image
Light Dispersion

Diffraction:

Light bends slightly around edges when it is obstructed. The spreading of a beam of light into the region behind an obstacle is known as diffraction. When we view a specimen, whether directly or with a microscope, the image seen is composed of a myriad of overlapping points of light emanating from the plane of the specimen. Therefore, the appearance and integrity of the image from a single point of light holds a significant amount of importance with regards to formation of the overall image. Because the image-forming light rays are diffracted, a single point of light is never really seen as a point in the microscope, but rather as a diffraction pattern containing a central disk or spot of light having a finite diameter and encircled by a fading series of rings. As a result, the image of a specimen is never an exact representation of the specimen, and a lower limit is imposed on the smallest detail in the specimen that can be resolved.

light diffraction illustration
Light Diffraction


Interference:

The colors produced by the interference of light waves at the front and back surfaces of very thin films are observed by reflection. Some natural substances have the property of double refraction, such as quartz, calcite and mica. Man-made devices such as diffraction gratings and others are often employed to produce interference effects. The phenomena of interference, like most of the other properties of light, are used in microscopy both as a tool to investigate object materials, or the phenomena produced naturally by the object material are interpreted as a characteristic.

Absorption:

The amount of light that is reflected from a transparent substance depends on the angle of incidence and the refractive index of the substance. At perpendicular incidence of a light beam only a part is reflected, the rest is being absorbed and transmitted. The amount of light absorbed depends on its thickness and the nature of the specimen. Absorption means the conversion of electromagnetic energy to heat energy.

absorption image illustration
Absorption

Polarization:

Polarized light is used as a tool or is interpreted as an object characteristic. Light vibrations restricted to a single plane are said to be plane-polarized. Polarized light microscopy is a useful method to generate contrast in birefringent specimens. The beautiful variety of colors displayed by specimens under crossed polarizers is a result of the interference between light waves passing through the specimen.

Excitation:

Certain substances when exposed to or excited by light continue to emit light a fraction of a second after removal of the exciting source. This property of a substance is known as fluorescence. Microscopic samples are excited with a fluorescence microscope. Fluorescence is a very powerful analytical tool in light microscopy.

Source: McLaughlin, Robert. Special Methods in Light Microscopy. London: Microscope Publications Ltd., 1977. Print.

Monday, February 3, 2014

Ciliates Swimming in Pond Water

This microscopy video was captured using the Motic BA310 biological microscope and a 3mp microscope camera. Notice the Ciliates swimming in the lower right hand corner of the video.