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

We review the current status of guided-wave optical communication devices. The operation and presently demonstrated performance characteristics of waveguides switches, modulators, filters, and polarization transforming devices are discussed. Emphasis is given to recent developments with very high speed modulators and polarization insensitive devices.

Guided-wave devices for optical communication

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

This paper reviews the field of high-speed small-aperture modulators for applications in optical communications, with emphasis on electrooptic modulation. The capabilities and limitations of electrooptic modulators are discussed based on a review of the physical origin of the electrooptic effect. Thermal and photoconduction phenomena, which may severely limit the operation of practical devices, are emphasized. The modulation power and bandwidth limitations using various schemes of electrooptic interaction are derived and compared. It is shown that lumped modulators are capable of efficient modulation for bandwidths up to about 1 GHz for visible wavelengths and are also attractive for their simplicity. For broader bandwidth capability the traveling wave or zigzag types of interaction become more efficient but with added complexity. Finally, acoustooptic and magnatooptic modulators are briefly discussed and compared with electrooptic modulators.

Modulators for optical communications

In order to realize the advantages of using lasers for communications, means must be obtained to modulate with sufficient bandwidth and capacity, deflect, switch, frequency translate, or otherwise effect a modification of the optical beam in a predictable manner. This problem has provided the incentive for extensive materials research directed toward the development of any crystal capable of low-loss optical transmission whose properties can be modified by an electric or magnetic field or applied external stress, and whose properties, at the same time, will interact in some specified manner with the optical beam. In this paper some dielectric materials for these uses currently in various stages of development will be described.

Dielectric materials for electrooptic, elastooptic, and ultrasonic device applications

Two light intensity modulators have been constructed using LiTaO3 and LiNbO3, respectively, in a reentrant microwave cav­ ity tuned to 4.2 GHz. The loop-coupled cavity is shown sche­ matically in Fig. 1. The crystal is attached to the chisel-shaped center post with silver paste and is oriented so that the (peak) voltage V is along the c axis. The cavity diameter D is 1.91 cm, the post diameter d is 0.38 cm and the resonant frequency is deter­ mined by the cavity height h. Not all the electric field is concentrated in the gap containing the crystal. A rough estimate of the added capacity Ca in paral­ lel with the crystal is ε0πD/4h. The ratio of total capacity CT to crystal capacity C is then

Performance of LiTaO(3) and LiNbO(3) light modulators at 4 GHz.

The purpose of this paper is to discuss the capabilities of a new high-speed encapsulated point-contact photodiode as a detector of microwave-modulated light. The laser-forming of germanium and silicon diodes and its influence on the diode characteristics is discussed. Measurements are presented on the static voltage-current characteristics for various light levels and on the small-signal microwave impedance characteristics of these diodes. These data show that the point-contact photodiode can have an effective device quantum efficiency greater than unity and an equivalent microwave impedance typically of several hundred to several thousand ohms. Data on the sensitivity of the diode as a direct demodulator of light which is intensity-modulated at 3 Gc/sec are also presented. It is shown that the silicon diode, operated at avalanche breakdown, is more sensitive than the germanium diode, and that both the germanium and silicon point-contact diodes are at least as sensitive as a good germanium surface-junction PIN photodiode. Finally, experimental results relating to the heterodyne mixing characteristics of the diodes are given when the diode is illuminated with microwave-modulated light and biased with a microwave local oscillator signal. Under these conditions it is found that the point-contact photodiode has greater sensitivity than that obtained previously using a simple bulk photoconductor.

High Speed Photodetection in Germainum and Silicon Cartridge-Type Point-Contact Photodiodes

This paper describes a method of evaluating the high frequency signal and noise performance of photodiodes suitable for mixers in an optical heterodyne receiver. The method uses a single laser beam modulated at a high frequency, 4 GHz, to simulate the signal and local oscillator in a conventional optical receiver thus avoiding the problem of aligning two separate optical beams; the results obtained can be applied to the design of an optical heterodyne receiving system. A new Schottky-barrier gallium arsenide photodiode is described, and measurements of a typical diode of this type are used as an example for comparison with theory. The photodiodes employed are of the same basic gold-dot epitaxial gallium arsenide type that has previously been used for millimeter wave and microwave mixers, but they have been modified to allow for the introduction of an optical beam from beneath the gold-dot contact area. A typical diode has a barrier capacitance of 0.027 pF, a series resistance of 30 Ω, and an effective quantum efficiency of 40%, which could be improved to perhaps 60% by an antireflection coating on the photodiode surface.

W. M. Sharpless

Papers

Performance of LiTaO(3) and LiNbO(3) light modulators at 4 GHz.

High Speed Photodetection in Germainum and Silicon Cartridge-Type Point-Contact Photodiodes

Evaluation of a Specially Designed GaAS Schottky-Barrier Photodiode Using 6328-A Radiation Modulated at 4 GHz.