AOTF - Acoustical Optical Tunable Filter: a crystal lattice device that allows light to pass through it when vibrated when ultra-sonic waves.  The frequency of the ultra-sonic sound waves control which wavelengths of light pass through the crystal and the duty cycle of the sonic pulses determine the percentage of the incident light that passes through the crystal.  AOTFs can have multiple inputs, so they can mix the input light together into one bean.  Light exiting an AOTF is polarized, hence when performing DIC imaging (Normarski) with laser illumination the analyzer plate should be removed from the light path.

PMT - photo multiplier tube: a vacuum tube light detector with gain.  Single photons cause the flow of current.  The amount of current is determined by the rate of photons entering the PMT and the voltage applied to the electrodes.  Gain is roughly proportional to applied voltage over the range of 100V to 1000V.  As the gain (voltage) becomes large (> 850 V) the amplification process becomes exponentially more noisy.

GAIN - Contrast - amplification: The gain of the Photo Multiplier Tube determines the range of light intensities that can be detected.  

OFFSET - Brightness - black level

DIC - Differential Interference Contrast viewing which is the same as Nomarski.  A mode of transmitted light microscopy that enhances differences of refractive index in samples.  A very good way of looking a transparent unstained colorless cells/samples.  DIC also improves resolution, contrast and reduces depth of view compared to conventional wide field microscopy, but not nearly as well as confocal imaging.  On the Leica Confocal DIC imaging may be performed while confocal scanning.  This is a good way of localizing fluorescent labels relative to a conventional view of the cell.

LASER - Light Amplification by Stimulated Emission of Radiation.  A light source which emits a thin coherent beam of light.  Coherent means the light beam does not diverge (much) and is polarized

Multipaged Tiff image file - A single TIFF format computer file that contains multiple images.  On the Leica Confocal such file end with .TIF rather than .tiff.  Tiff files can not be viewed completely by most image processing software. Only the first page is displayed.  Note that Wang Image or Kodak Image on Windows operating systems can view all the images in a multipaged tiff image file.

Nomarski - same as DIC.  See DIC.

t-series - time lapse images.  On LeicaTCS-NT a time lapse series of images are stored as one TIFF file.  This is a multipaged tiff file that can not be directly open by most computer imaging software.

z-series - serial sections gathered in the focal axis (z-axis).  On LeicaTCS-NT a z-series images are stored as one multipaged TIFF file.


Field Iris
Stokes shift
Airy disk
Focal Plane
Real image
Virtual Image
Resolution - 
Optical section - 
Numerical Aperture
Dynamic range
Signal averaging
LeicaTCS-NT - Leica True Confocal Scanning - running with WindowsNT.  Must be a term generated by the marketing department.
LUT - Look Up Table: a translation table that is used to convert gray intensities into colors or change the gray scale
Novel - Netware
Bitmap - bmp
Byte - 8 bits of binary information.  e.g. 8 pieces of yes or no information.
MByte        - MB  -  1024^2     -  2^20
KiloByte     - KB   -  1024         -  2^10
GigaByte     - GB   -  1024^3     -  2^30
LCSM - Laser Scanning Confocal Microscopy
MPLSCM - Multiphoton Laser Scanning Confocal Microscopy


Icon_Inverted_Laser.GIF (1500 bytes) Icon_book_white.gif (1143 bytes) 1998-2003 Michael Chua, Cell & Molecular Physiology, UNC.  All rights reserved. 
To Confocal Homepage To Operating the confocal To Booking the confocal Go back a page Comments: Dr. Michael Chua