This is a continuation from the previous tutorial - Camera Lenses   1. INTRODUCTION   Historic Overview The optical principles and basic lens design needed to generate a diffraction-limited, highly magnified image with the light microscope were already essentially perfected a century ago. Ernst Abbe demonstrated how a minimum of two successive orders of diffracted light had to be captured in order for a particular spacing to be resolved (see historical sketch about Abbe principle). Thus, he explained and demonstrated with beautiful experiments the role of the wavelength of the i ..read more

This is a continuation from the previous tutorial - Cameras   1.  INTRODUCTION Camera lenses have been discussed in a large number of books and articles. The approach in this chapter is to concentrate on modern types and to describe imaging performance in detail both in terms of digital applications and in terms of the optical transfer function. By modern types, we mean lens forms that were found on cameras in 1992. The chapter deals almost entirely with lenses for the 35-mm (24 \(\times\) 36-mm) format. This limitation is unfortunate but not really inappropriate, given the wide ..read more

This is a continuation from the previous tutorial - Liquid Crystals.   1. Introduction Thanks to technical progress and vigorous competition , the camera buyer faces a difficult challenge in making a choice. This chapter will attempt to reduce the difficulty by asking the buyer to consider the final image; its purpose, its audience, and its appearance. Next, some of the more recent technical features are discussed. These include the intriguing ability to select objects in a scene for focus and/ or exposure measurement by tracking the position of the user’s eye. Finally, various types of c ..read more

This is a continuation from the previous tutorial - an introduction to optical beams and resonators.   1. Introduction A fundamental building block of modern coherent optical transport system is the timing recovery or timing synchronization circuit. Recovering the transmitted clock from the received signal is a first step in recovering the data. Only when the receive-side VCO (voltage-controlled oscillator) is phase-locked to the transmit-side VCO, the other DSP functions such as equalization and carrier recovery can commence. A typical receiver acquisition sequence will start with lockin ..read more

This is a continuation from the previous tutorial - metal-coated fibers.   1. Transverse Modes in Optical Resonators Laser cavities differ in several significant ways from the closed microwave cavities that are commonly treated in electromagnetic theory textbooks. Optical resonators first of all usually have open sides, and hence always have diffraction losses because of energy leaking out the sides of the resonator to infinity. Optical resonators are also usually described in scalar or quasi plane-wave terms, with emphasis on the diffraction effects at apertures and mirror edges, rather ..read more

This is a continuation from the previous tutorial - acousto-optic devices and applications.   1. Introduction An optical fiber has to be defended by some protective coating from mechanical damage during handling and from environmental factors during its use. In many cases, a polymer coating is appropriate for enough protection. However, there are a number of special applications of optical fibers in which ordinary polymer-coated fibers cannot be used. These applications can be divided into several groups: Increased reliability (hermeticity of the coating is important) High vacuum (when o ..read more

This is a continuation from the previous tutorial - nonlinear compensation for digital coherent transmission.   1. Introduction When an acoustic wave propagates in an optically transparent medium, it produces a periodic modulation of the index of refraction via the elasto-optical effect. This provides a moving phase grating which may diffract portions of an incident light into one or more directions. This phenomenon, known as the acousto-optic (AO) diffraction, has led to a variety of optical devices that perform spatial, temporal, and spectral modulations of light. These devices have bee ..read more

This is a continuation from the previous tutorial - laser oscillation dynamics and oscillation threshold.   1. Introduction The degree to which fiber impairments are compensated determines the transmission capacity of fiber-optic transmission systems. Dispersion-compensating fiber (DCF) is commonly used to compensate chromatic dispersion.Wavelength-division multiplexing (WDM) systems suffer from both intra- and interchannel nonlinearities such as cross-phase modulation (XPM) and four-wave mixing (FWM). These effects can be suppressed using dispersion management. Compensation of nonlinear ..read more

This is a continuation from the previous tutorial - X-ray optics.   1. Introduction Hermetically coated optical fibers have a thin layer of an impervious material applied over the surface of the glass fiber. Hermetic coatings are used to improve the reliability of fibers by preventing strength degradation caused by moisture attack on the fiber surface, and by preventing the diffusion of hydrogen into the core of the fiber. The typical polymer coatings that are used on optical fibers are able to prevent liquid water from contacting the glass surface but are not able to stop the diffusion o ..read more

This is a continuation of the previous tutorial - digital equalization in coherent optical transmission systems.   1. Introduction The following fundamental difficulties have served as a deterrent to the development of x-ray imaging systems: Adequate sources and detectors have not always been available; No suitable refractive material exists from which conventional x-ray lenses can be fabricated; Mirrors have traditionally exhibited useful reflectances only for grazing incident angles; Grazing incidence optical designs are cumbersome and difficult to fabricate and align; Scattering effec ..read more