Difference between revisions of "Examination"
From Glossary of Forensic Document Examination & Pattern Recognition
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The examination is the act of making a close and crucial study of any material, and with questioned documents is the process necessary to discover the facts about them. Various types of examination are undertaken including microscopic, visual, photographic, chemical, ultraviolet and infrared document examinations. | The examination is the act of making a close and crucial study of any material, and with questioned documents is the process necessary to discover the facts about them. Various types of examination are undertaken including microscopic, visual, photographic, chemical, ultraviolet and infrared document examinations. | ||
| + | ==Type of examinations== | ||
;Microscopic examination: Any study or examination made with the microscope in order to discover minute physical details. | ;Microscopic examination: Any study or examination made with the microscope in order to discover minute physical details. | ||
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;Oblique light examination: Any examination with the illumination so controlled that it grazes or strikes the surface of the document from one side at a very low angle; also referred to as side light examination. | ;Oblique light examination: Any examination with the illumination so controlled that it grazes or strikes the surface of the document from one side at a very low angle; also referred to as side light examination. | ||
| + | ;Transmitted light examination: An examination in which the document is viewed with the source of illumination behind it and the light passing through the paper. | ||
| + | ;Ultraviolet examination: Ultraviolet radiation is invisible and occurs in the wavelengths just below the visible blue-violet end of the color spectrum. The invisible rays react on some substances so that visible light is emitted, a phenomenon known as ultraviolet fluorescence. Thus, ultraviolet examination may be made visually or photographically, by recording either the reflected ultraviolet or visible radiation. | ||
Latest revision as of 11:21, 12 December 2012
The examination is the act of making a close and crucial study of any material, and with questioned documents is the process necessary to discover the facts about them. Various types of examination are undertaken including microscopic, visual, photographic, chemical, ultraviolet and infrared document examinations.
Type of examinations
- Microscopic examination
- Any study or examination made with the microscope in order to discover minute physical details.
- Oblique light examination
- Any examination with the illumination so controlled that it grazes or strikes the surface of the document from one side at a very low angle; also referred to as side light examination.
- Transmitted light examination
- An examination in which the document is viewed with the source of illumination behind it and the light passing through the paper.
- Ultraviolet examination
- Ultraviolet radiation is invisible and occurs in the wavelengths just below the visible blue-violet end of the color spectrum. The invisible rays react on some substances so that visible light is emitted, a phenomenon known as ultraviolet fluorescence. Thus, ultraviolet examination may be made visually or photographically, by recording either the reflected ultraviolet or visible radiation.
