static contrast ratio

Examples of static contrast ratio in the following topics:

• Resolution of the Human Eye

  • The retina of human eye has a static contrast ratio of around 100:1 (about 6.5 f-stops).
  • Hence, a dynamic contrast ratio of about 1,000,000:1 (about 20 f-stops) is possible.

• Pascal's Principle

  • Pascal's Principle states that pressure is transmitted and undiminished in a closed static fluid.
  • Pascal's Principle (or Pascal's Law) applies to static fluids and takes advantage of the height dependency of pressure in static fluids.
  • As a result of Pascal's Law, the pressure change (pressure applied to the static liquid) is transmitted undiminished in the static liquid so that the applied pressure is 2 N/m2 at the bottom of the bottle as well.
  • For a hydraulic press, the force multiplication factor is the ratio of the output to the input contact areas.
  • Two different types of hydraulic press configurations, the first in which there is no difference in height of the static liquid and the second in which there is a difference in height Δh of the static liquid.

• Application of Bernoulli's Equation: Pressure and Speed

  • For "ideal" flow along a streamline with no change in height, an increase in velocity results from a decrease in static pressure.
  • The kinetic energy of the fluid is stored in static pressure, $p_s$, and dynamic pressure, $\frac{1}{2}\rho V^2$, where \rho is the fluid density in (SI unit: kg/m3) and V is the fluid velocity (SI unit: m/s).
  • The SI unit of static pressure and dynamic pressure is the pascal.
  • Static pressure is simply the pressure at a given point in the fluid, dynamic pressure is the kinetic energy per unit volume of a fluid particle.
  • The Mach number represents the ratio of the speed of an object moving through a medium to the speed of sound in the medium.

• Examples and Applications

  • The particles are held to a spiral trajectory by a static magnetic field and accelerated by a rapidly varying (radio frequency) electric field.
  • Mass spectrometry is an analytical technique that measures the mass-to-charge ratio of charged particles.
  • Mass analyzers separate the ions according to their mass-to-charge ratio.
  • The deflections of the particles are dependent on the mass-to-charge ratio.
  • This one is for the measurement of carbon dioxide isotope ratios (IRMS) as in the carbon-13 urea breath test.

• NMR and MRIs

  • After the electromagnetic field is turned off, the rotations of the hydrogen protons return to thermodynamic equilibrium, and then realign with the static magnetic field.
  • MRI shows a marked contrast between the different soft tissues of the body, making it especially useful in imaging the brain, the muscles, the heart, and cancerous tissue—as compared with other medical imaging techniques such as computed tomography (CT) or X-rays.
  • MRI contrast agents may be injected intravenously to enhance the appearance of blood vessels, tumors or inflammation.

• What is a Fluid?

  • These properties are typically a function of their inability to support a shear stress in static equilibrium.
  • In contrast, ideal fluids can only be subjected to normal, compressive stress (called pressure).

• Electric vs. Magnetic Forces

  • Below we will quickly review the two types of force and compare and contrast their effects on a charged particle.
  • Recall that in a static, unchanging electric field E the force on a particle with charge q will be:
  • In contrast, recall that the magnetic force on a charged particle is orthogonal to the magnetic field such that:

• Problems

  • A particle of mass $m$, charge ${q}$, moves in a plane perpendicular to a uniform, static, magnetic field $B $.
  • Calculate the total energy radiated per unit time, expressing it in terms of the constants already defined and the ratio $\gamma=1/\sqrt{1-\beta^2}$ of the particle's total energy to its rest energy.You can assume that the particle is ultra-relativistic.

• B.3 Chapter 3

  • A particle of mass $m$, charge $q$, moves in a plane perpendicular to a uniform, static, magnetic field $B$.
  • Calculate the total energy radiated per unit time, expressing it in terms of the constants already defined and the ratio $\gamma=1/\sqrt{1-\beta^2}$ of the particle's total energy to its rest energy.

• Color Vision

  • The U and V components may be sampled at a lower rate than Y (due to narrower bandwidth) and may be quantified more coarsely (due to lower contrast sensitivity).
  • The vertical scale is the contrast sensitivity of human vision, which is the ratio of the maximum visible range of intensities to the minimum discernible peak-to-peak intensity variation at the specified frequency.