In the forensic science field there are various machines used to examine physical evidence. One of those instruments is the scanning electron microscope (SEM). This instrument can be used in examining physical evidence found at crime scenes. There have been a number of scientists that have developed and improved the SEM. SEM is very significant in forensics because it can narrow down size, shape, and chemical composition. The scanning electron microscope is always growing and becoming a great impact on forensic science.
We will start of learning where the scanning electron microscope (SEM) began. Knoll built the first scanning microscope in 1935; he was not using demagnifying lenses. Von Ardenne expressed the theoretical philosophy underlying the scanning electron microscope. Developing the first scanning electron microscope in 1942 was Zworykin. This microscope was more improved due to using an electron multiplier tube as a preamplifier off the secondary electrons emission current. The resolution on the SEM was 50 nm (Physics Emory). Improving the SEM that Zworykin had developed, Oatley used nonlinear signal amplification. He was also the first to place in a stigmator in the SEM, which was used to correct lens cylindrical imperfections. In 1960, Everhart and Thornley improved the secondary electron detection. Three years following that Pease and Nixon, combined all the improvements in one microscope. The first commercial scanning electron microscope was developed in 1965 by the Cambridge Scientific Instruments Mark I (Physics Emory).
The scanning electron microscope has 10 parts to it which are the secondary detector, x-ray detector, backscatter detector, sample chamber, objective lens, electron beam, condenser lens, anode, ...
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...nated is very significant in criminal cases. We have reviewed the history and parts of the SEM, how it works, how it can aid in solving cases, and an actual case it was used to find the murderer. Scanning electron microscope is very significant and it will continue to be in the future.
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Physics Emory. (n.d.). Retrieved from Physics Emory: http://www.physics.emory.edu/~weeks/lab/papers/bogner-micron07.pdf
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2. A trio of Dutch eyeglass makers invented the microscope in the late 1500’s. It consisted of a tube with lenses ground from rock crystal, and it magnified objects up to 9 times their actual size.
Therefore, the criminal justice system relies on other nonscientific means that are not accepted or clear. Many of forensic methods have implemented in research when looking for evidence, but the methods that are not scientific and have little or anything to do with science. The result of false evidence by other means leads to false testimony by a forensic analyst. Another issue with forensic errors is that it is a challenge to find a defense expert (Giannelli, 2011). Defense experts are required to help the defense attorneys defend and breakdown all of the doubts in the prosecutors scientific findings in criminal cases. Scientific information is integral in a criminal prosecution, and a defense attorney needs to have an expert to assist he/she in discrediting the prosecution (Giannelli,
“Advance in Forensics Provide Creative Tools for Solving Crimes.” www.ctcase.org. Np. n.d. Web. 17 March 2014.
The science of statistics refers to two distinct areas of knowledge. One area refers to the analysis of uncertainty and the other area refers to the listing of events, counts of entities for various economic, social, and scientific purposes. It is for these reasons that statistics can be of great value within the area of forensic science. Evidence that is used within a legal setting, contains doubt, which means that this evidence requires some statistical and problematic reasoning which plays an imperative role in the criminal investigation, prosecution and trial. Statistical and problematic reasoning also plays a major part in relation to forensic scientific evidence, such as DNA, which is produced by an expert witness.
The specimen's views were different every time because each of the microscopes had a different view of each object. Dissecting Microscope looks blurred looking and pale color. Compound Light Microscope looks blurry looking and grows differently when you change the zoom or size. Transmission Electron Microscope looks grayish (black and white) and shows a lot of the structure of the specimen. Scanning Electron Microscope looks like a 3-D black and white shaped specimen. A leaf under a dissecting microscope would be described as this if you zoom in and out, you would see blurry, clear, then blurry again and it was bright then pale colors. Blood under a compound light microscope would be described as this if you look at it, it would be a blur and sometimes clear shape depends on the zoom in or out. Algae under a transmission electron microscope would be described as this if you look at it, it would be grayish different look by the shape and detailed with the structure of the thing. A leaf under a scanning electron microscope would be described as this if you zoom in and out, you would see blurry 3-D black and white with lots of detail of the
[10] "The Transmission Electron Microscope." Nobelprize.org. Nobel Web AB, 2010. Web. 10 July 2010. .
The invention of the camera and its many makeovers has changed the art of photography. The idea for photography came around in 1814 when Joseph Niépce wanted an image of his son before he left for war. He succeeded in making the first camera in 1827, but the camera needed at least eight hours to produce one picture. Parisian Louis Daguerre invented the next kind of camera in 1839, who worked with Niépce for four years. His camera only took fifteen to thirty minutes to produce a picture.
Forensic Science, recognized as Forensics, is the solicitation of science to law to understand evidences for crime investigation. Forensic scientists are investigators that collect evidences at the crime scene and analyse it uses technology to reveal scientific evidence in a range of fields. Physical evidence are included things that can be seen, whether with the naked eye or through the use of magnification or other analytical tools. Some of this evidence is categorized as impression evidence2.In this report I’ll determine the areas of forensic science that are relevant to particular investigation and setting out in what method the forensic science procedures I have recognized that would be useful for the particular crime scene.
methods when examining crimes scenes or looking at evidences in labs then many cases would be lost in
The transitional growth in the forensic science sector has not been without challenges. Though the world has experienced increased capabilities and scientific knowledge, which has led to faster investigations and results, many forensic experts have argued that forensic laboratory testing, in the light of 21st century technological advancements, is yet to meet the expected rate in quick available testing and analysis (Mennell & Shaw, 2006). This is with respect to the growing rate of crime and the high demand of quick crime scene testing and analysis. In the science of crime scene, analysis and interpretation of evidence is majorly dependent on forensic science, highlighting the change in the role of forensic sciences (Tjin-A-Tsoi, 2013). In the business of forensic science, time is beginning to play important role in the evidence testing and analysis which is becoming crucial in reducing ...
How Cryonics Works. In Science How Stuff Works. Retrieved December 29, 2013, from http://science.howstuffworks.com/life/genetic/cryonics2.htm Best, B. n.d. - n.d. - n.d. Cryonics Frequently Asked Questions. By Ben Best.
As far back as 1832, James Marsh was the first to use forensics at trial to give evidence as a chemist in 1832. Since that time forensic science and evidence has come a long way in various ways and technology to help in determine if the suspect is guilt or not, through such things as DNA testing, blood, and fingerprints. The first forensic police crime lab was created in 1910. The contributions of Dr. Edmond Locard, a French scientist and criminologist, proposed that “everything leaves a trace”. This principle is still valid today as it was so many years ago. No matter how small, the specialized trained technicians and investigators can take these methods and go to a crime scene to get evidence. “Forensic science is the application of sciences such as physics, chemistry, biology, computer science and engineering to matters of law.” (Office of Justice, 2017) These different sciences can help achieve and assist in solving a case. Forensic science has also the ability to prove that a crime was committed, it can find the elements of the crime, it can help place the suspect at the scene and whether the suspect had any contact with the victim. However, in the last several years the techniques and with the use of technology the evidence that forensic science uncovers can also exonerate an innocent individual who has been falsely accused of the
The science of forensics is now recognized as a critical ingredient in law enforcement and the solution of crimes. Protecting a crime scene from contamination and gathering and interpreting evidence accurately have become some of the most critical ingredients in crime solving. Advances in technology are being applied to the finite and exacting field of forensic science, a field in which technical competency is achieved only by synthesis of a number of factors including training, experience, supervision, continuing education, proficiency and an application of scientific methods and protocols against a background of stringent professional ethics. (Division of State Police)
“The word ‘forensics’ means “connected with the courtroom”; so forensic science is, therefore, concerned with gathering hard evidence that can be presented in a trial” (Innes 9). Forensic science is a science that is applied specifically to legal matters, whether criminal or civil. “Few areas in the realm of science are as widespread and important as forensic science” (Hunter 12). Forensics is the one science that is most commonly used in everyday life. It is also a branch of science that incorporates other branches of science such as biology, chemistry, and etc. Since it is used almost every day “No one can dispute the importance of the contributions to society made by forensic science; the ability to solve crime is undeniably important” (Hunter 13). Forensic science has given criminal investigation a new edge. “Advances in science have opened the door for more effective evidence discovery, howev...
...s an essential part to solving crimes. We are fortunate to live in an exciting day and age where education, and technology, and society is rapidly evolving and changing. Thanks to that, the future for forensics is looking up and although, as mentioned earlier the media exaggerates forensics, it is striking interest in a lot more people. The public is hungry for information about our legal system, particularly in forensics. As long as The National Institute of Justice, and other organizations continue to fund and support forensic science, we will be able to improve our justice system significantly. We also wouldn’t be where we are today with forensics if it wasn’t for people like Locard, who devoted their time and energy into this field of work. As much as we may overlook it, forensic science is important in our society and it can help us understand more about crime.