Foundations of Confocal Scanned Imaging in Light Microscopy -- Fundamental Limits in Confocal Microscopy -- Special Optical Elements -- Points, Pixels, and Gray Levels: Digitizing Image Data -- Laser Sources for Confocal Microscopy -- Non-Laser Light Sources for Three-Dimensional Microscopy -- Objective Lenses for Confocal Microscopy -- The Contrast Formation in Optical Microscopy -- The Intermediate Optical System of Laser-Scanning Confocal Microscopes -- Disk-Scanning Confocal Microscopy -- Measuring the Real Point Spread Function of High Numerical Aperture Microscope Objective Lenses -- Photon Detectors for Confocal Microscopy -- Structured Illumination Methods -- Visualization Systems for Multi-Dimensional Microscopy Images -- Automated Three-Dimensional Image Analysis Methods for Confocal Microscopy -- Fluorophores for Confocal Microscopy: Photophysics and Photochemistry -- Practical Considerations in the Selection and Application of Fluorescent Probes -- Guiding Principles of Specimen Preservation for Confocal Fluorescence Microscopy -- Confocal Microscopy of Living Cells -- Aberrations in Confocal and Multi-Photon Fluorescence Microscopy Induced by Refractive Index Mismatch -- Interaction of Light with Botanical Specimens -- Signal-to-Noise Ratio in Confocal Microscopes -- Comparison of Widefield/Deconvolution and Confocal Microscopy for Three-Dimensional Imaging -- Blind Deconvolution -- Image Enhancement by Deconvolution -- Fiber-Optics in Scanning Optical Microscopy -- Fluorescence Lifetime Imaging in Scanning Microscopy -- Multi-Photon Molecular Excitation in Laser-Scanning Microscopy -- Multifocal Multi-Photon Microscopy -- 4Pi Microscopy -- Nanoscale Resolution with Focused Light: Stimulated Emission Depletion and Other Reversible Saturable Optical Fluorescence Transitions Microscopy Concepts -- Mass Storage, Display, and Hard Copy -- Coherent Anti-Stokes Raman Scattering Microscopy -- Related Methods for Three-Dimensional Imaging -- Tutorial on Practical Confocal Microscopy and Use of the Confocal Test Specimen -- Practical Confocal Microscopy -- Selective Plane Illumination Microscopy -- Cell Damage During Multi-Photon Microscopy -- Photobleaching -- Nonlinear (Harmonic Generation) Optical Microscopy -- Imaging Brain Slices -- Fluorescent Ion Measurement -- Confocal and Multi-Photon Imaging of Living Embryos -- Imaging Plant Cells -- Practical Fluorescence Resonance Energy Transfer or Molecular Nanobioscopy of Living Cells -- Automated Confocal Imaging and High-Content Screening for Cytomics -- Automated Interpretation of Subcellular Location Patterns from Three-Dimensional Confocal Microscopy -- Display and Presentation Software -- When Light Microscope Resolution Is Not Enough:Correlational Light Microscopy and Electron Microscopy -- Databases for Two- and Three-Dimensional Microscopical Images in Biology -- Confocal Microscopy of Biofilms — Spatiotemporal Approaches -- Bibliography of Confocal Microscopy.

Handbook of biological confocal microscopy

This paper is concerned with a systematic approach to the design of the “linear channel” of a repeater for a digital fiber optic communication system. In particular, it is concerned with how one properly chooses the front-end preamplifier and biasing circuitry for the photodetector; and how the required power to achieve a desired error rate varies with the bit rate, the received optical pulse shape, and the desired baseband-equalized output pulse shape. It is shown that a proper front-end design incorporates a high-impedance preamplifier which tends to integrate the detector output. This must be followed by proper equalization in the later stages of the linear channel. The baseband signal-to-noise ratio is calculated as a function of the preamplifier parameters. Such a design provides significant reduction in the required optical power and/or required avalanche gain when compared to a design which does not integrate initially. It is shown that, when the received optical pulses overlap and when the optical channel is behaving linearly in power,1 baseband equalization can be used to separate the pulses with a practical but significant increase in required optical power. This required power penalty is calculated as a function of the input and equalized pulse shapes.

Receiver design for digital fiber optic communication systems, II

Receiver design for digital fiber optic communication systems. I

The characteristics of high-sensitivity photodetectors suitable for wide bandwidth optical communication systems are summarized. Photodiodes, photomultipliers, and photoconductive detectors for wavelengths from 0.3 µm to 10.6 µm are covered. The use of internal current gain by means of avalanche and electron multiplication and by means of optical heterodyne detection to increase sensitivity of high speed photodetectors is discussed. The application to visible and infrared laser communication systems is reviewed.

Photodetectors for optical communication systems

Publisher Summary This chapter describes the performance limitations of Si PIN detectors and avalanche photodiodes so that a decision regarding which device to employ can be based on the system requirements. The chapter discusses the basic properties of these devices, for applications that require an avalanche photodiode, and summarizes the performance of avalanche photodiodes in various materials, pointing outareas where further research would be particularly fruitful. This exploration should first be directed toward finding a semiconductor with the appropriate energy gap that has a large asymmetry of the electron and hole ionization coefficients. Only after this is done should additional effort in materials and device technology, which are necessary to obtain high performance avalanche photodiodes, be considered.

Chapter 5 Avalanche Photodiodes

A new germanium photodiode having an extremely uniform quantum efficiency from the visible to 1.65 μ has been developed. The device consists of a lithium-drifted junction in which the light enters in a direction parallel to the junction, thereby allowing absorption path lengths of several centimeters, if desired, with essentially zero dead layer. Sensitive areas up to about 10 mm in one dimension and several centimeters in the other dimension are possible. Typical characteristics for a device 2 cm long having a sensitive area 7 mm × 7 mm are: diode capacitance, 3 pF; charge collection time, 75% of charge collected in 25 nsec at 500 V; measured NEP, 3.7 × 10−15WHz−12 at 1.625 μm and 77 K for frequencies up to 30 kHz, and 5.5 × 10−13WHz−12 at 1.625 μm and 195 K for frequencies up to 40 kHz. At low frequencies, the detectivity can be background limited by 300-K blackbody radiation. The device must be used and stored at reduced temperatures. A convenient cryostat, capable of maintaining the device at or near 77 K for 150 h without refilling, is described.

R.J. McIntyre

Papers

A new germanium photodiode with extended long-wavelength response.

A new germanium photodiode with extended long-wavelength response