Glossary of Terms
100
•
CCD Read Noise (
e
ccd read noise )
Noise that is generated by the CCD’s on-chip output amplifier. This noise
parameter is frequency dependent and will increase with increased pixel
processing times.
•
CCD Dark Noise (
e
ccd dark noise )
Noise that is generated due to the random statistical variations of the dark current
and is equal to the square root of the dark current. It should be noted that dark
current can be subtracted from an image or spectra and will not contribute to the
total system noise; however, the dark noise remains. In addition, cooling the array
can significantly reduce the accumulation of dark current and its associated dark
noise.
•
CCD Shot Noise (
e
ccd shot noise ):
Noise that is generated due to the random statistical variations associated with
light. Shot noise is equal to the square root of the number of electrons generated.
Photoelectric Effect
Some materials respond to light by releasing electrons. When light of sufficient
energy hits a photosensitive material, an electron is freed from being bound to a
specific atom. Such materials include the P-N junctions of the silicon photodiodes
used in CCD arrays. The energy of the light must be greater than or equal to the
binding energy of the electron to free an electron. The shorter the wavelength, the
higher the energy the light has.
Photoelectron
A photoelectron is an electron that is released through the interaction of a photon with
the active element of a detector. The photoelectron could be released either from a
junction to the conduction band of a solid-state detector, or from the photocathode to
the vacuum in a PMT. A photoelectron is indistinguishable from other electrons in
any electrical circuit.
Photo Response Nonuniformity (PRNU)
PRNU is the peak-to-peak difference in response between the most and least sensitive
elements of an array detector, under a uniform exposure giving an output level of
V
Sat
/2. These differences are primarily caused by variations in doping and silicon
thickness.
Quantum Efficiency (QE)
The efficiency of a detector’s photoelectric effect is quantified by the ratio of the
number of photoelectrons produced to the number of photons impinging on the
CCD’s photoactive surface. For example, a QE of 20% would indicate that one
photon in five would produce a distinguishable photoelectron.
Summary of Contents for JOBIN YVON SYNAPSE
Page 1: ...SYNAPSE CCD Detection System User Manual Part Number 81100 Revision 2...
Page 10: ...Preface x...
Page 14: ...System Description and Specifications 4...
Page 28: ...Detector System Installation 18...
Page 38: ...Initial Power up and Operation 28...
Page 48: ...Temperature Control 38...
Page 72: ...Appendix A Dimensional Drawings 62 Figure 17 Distance from Focal Plane to CCD Chip...
Page 73: ...Appendix A Dimensional Drawings 63 Figure 18 Synapse Power Supply Unit...
Page 74: ...Appendix A Dimensional Drawings 64...
Page 86: ...Appendix C Performing Routine Procedures with SynerJY 76...
Page 100: ...Appendix E Accessories 90...
Page 104: ...Warranty 94...
Page 113: ...103 Notes...
Page 114: ...104 Notes...