Principles Of Photonics And Optical Engineering

b. Describe the spectral curve of each target type with respect to its absorption and reflectance characteristics. (3)

The concentrations and absorbances of the red and blue dyes were used to find the concentration of the purple dyes. From the graph of the blue dye, the linear equation for absorbance was y = mx + b. From that formula came the equation y = 7.915 x 104 (x) + 0.02489, where y represents absorbance, m is slope, x is concentration/molarity, and b is the constant/y-intercept. The same set up was performed for the red dye, but the equation produced was y = 1.045 x 104 (x) +.001298. The equations found when graphing absorbance vs. concentration were used to find the concentration of the purple dyes. The absorbance for purple dye 3 on the red wavelength of 470 nm equaled 0.149 and 0.818 for the blue wavelength of 635 nm. For purple dye 1

From this graph and chart we can see that the higher the concentration the higher the absorbance, all the different concentrations were tested at the same wavelength (625nm). Also we can determine our unknown substances concentration by using the absorbance we got for it. The red dot on the graph followed by the line towards the horizontal axis indicates that the concentration of fast green was 34% or 5.1x10-3.

Scientists use an instrument called a spectrometer to quantitatively determine the amount of light absorbed by a solution. The primary inner parts of a typical spectrometer are described below. The spectrometer has a light source that emits white light containing a vast mixture of different wavelengths of electromagnetic radiation. The wavelength of interest is then selected using a monochromator (“mono” meaning one and “chromate” meaning color) and an additional exit slit. The separation of white light into different colors (wavelengths) is known as diffraction. The selected light then reaches the sample and depending on how the light interacts with the chemical compound of interest, some of the light is absorbed and some passes straight through. By comparing the amount of light entering the sample (P0) with the amount of light reaching the detector (P), the spectrometer is able to tell how much light is absorbed by the sample.

A = Absorbance difference  = Molar extinction coefficient C = Concentration L = Path length

Sof-Optics is a small (specialty-niche) player in a $155M contact-lens market. (Three competitors occupy 75% of this market (Bausch + Lomb (51%), American Optical (14%), Continuous Curve (10%); approximately twenty players (including Sof-Optics’ ~3%) occupy the remaining 25%.) This consumer space is already appreciable in size (~5M contact-lens wearers in 1980), and promises exponential growth in future years (only 10% of ~50M prospective lens-wearers in America have even tried soft contact lenses).

The highly conjugated system of the cyanine dyes makes it a very good compound in the development of more efficient solar cells. In this experiment, the maximum wavelength was measured for nine dyes using a UV-Vis spectrum. The result that were obtained agreed with Kuhn’s model for the less polarizable end groups such as 3,3 '-diethyloxadicarbocyanine and 3,3 '-diethyloxatricarbocyanine. That suggested that these two compounds were not as easy to polarize compared to the rest of the dyes. The rest of the dyes required the use of the empirical parameter α to provide more reliable predictions of the wavelengths. This was due to the highly polarized ends of the dyes which needed the adjustment of the parameter to get more accurate results. The series with the higher polarizable end groups’ absorbed higher wavelength light than the less polarized groups. This supported the idea of the one-dimensional box. Also, higher wavelength was determined to be associated with longer conjugated carbon methine chains between the Nitrogen atoms. Kuhn’s free electron model was very reliable for this system.

The ending result of this experiment confirms that as five test tubes are lined up with the varying level of absorbance, different results in the level of absorbance will appear as well, this is visible in above table. Thus, this is due to the varying amount of water in the solution. The blank sample had a 0.30 in its level of absorbance.

transmittance (T) represents the fraction of the original radiant energy that passes through, or is

Chapter 15 is broken into three different sections; Interference, Diffraction, and Lasers. Throughout the chapter there are various real world examples. This chapter introduces the vocabulary words: coherence, path difference, order number, diffraction, resolving power, and laser. There are inphase and outphase.

The amount of refraction on the lens depends on the wavelength so different wavelengths focus at slightly different places. This is chromatic aberration, a problem where a rainbow halo appears around images.

The index of refraction is the ratio of the speed of light in a vacuum to the speed of light in the medium: n = c / v

Introduction Photonic crystals are special class of optical media with periodic modulation of refractive index by arrangement of dielectric material. They respond to light waves over a desired range of frequencies by perfectly reflecting them or allowing them to propagate only in certain directions or confining them within a specified volume. Photons either propagate through this structure or they don 't. Frequencies that propagate are called modes, and groups of allowed modes form bands. Disallowed bands of frequencies are called photonic band gaps. This property of photonic bandgap is utilised to manipulate light propagation. In particular, we can design and construct photonic crystals with photonic band gaps, preventing light from propagating in certain directions with specified frequencies

There have been extensive research in field the integrated photonics and industry in recent years. There photonic circuits are advantageous as compared to conventional electronic circuits in a vast range of applications.. Therefore, so much research have been done on photonic devices, such as HCGs and photonic crystal based hollow waveguides, Bragg reflectors and their integrations with electronic devices.

The absorption of radiation can elevated in the energy of the molecule. The energy obtained by the molecule which directly proportional to the wavelength of radiation. When the energy of molecules gets higher, it will leads to the electronic excitations where electrons excites to higher energy levels. A certain wavelength that a given molecule can absorb based on the changes in vibrational, or rotational or electronic