1. a. Why are excimer lasers particularly useful in microsurgical
applications?b. The absorption curves shown in Figure 28-1 begin at a
wavelength of 0.4 μm, which is longer than the wavelengths of the
excimer lasers. Do some research to find the absorption characteristics
of water and hemoglobin at the wavelengths of the excimer lasers.c.
Considering your findings in part (b), discuss the utility of the
excimer laser as a scalpel and for photocoagulation. Get solution
2. After doing some research, summarize the current state of the art with regard to the development of fibers through which excimer lasers can propagate with low loss. Get solution
3. Consider the medical procedure called posterior capsulotomy, illustrated in Figure 28-2 and discussed in the text surrounding that figure. Using the analytical tools developed in Chapter 27, choose a lens focal length, a beam-waist spot size at the lens, and a lens-to-cornea distance for use in the procedure. Be sure to respect the 17° convergence angle requirement indicated in the caption to Figure 28-2. For the system you design, calculate the beam-waist spot size at the focused spot, and the Rayleigh range parameter (z0) for the focused beam. Comment on the importance of the Rayleigh range in this design problem. It may be useful to refer to the schematic eye shown in Figure 19-3. Get solution
4. For the system designed in problem 1, find the irradiance at the center of the focused beam waist for an Nd:YAG laser of pulse energy 4 mJ and pulse width 1 ns. Compare the answer obtained with the estimate given in Example 28-1.Problem 1Consider the medical procedure called posterior capsulotomy, illustrated in Figure 28-2 and discussed in the text surrounding that figure. Using the analytical tools developed in Chapter 27, choose a lens focal length, a beam-waist spot size at the lens, and a lens-to-cornea distance for use in the procedure. Be sure to respect the 17° convergence angle requirement indicated in the caption to Figure 28-2. For the system you design, calculate the beam-waist spot size at the focused spot, and the Rayleigh range parameter (z0) for the focused beam. Comment on the importance of the Rayleigh range in this design problem. It may be useful to refer to the schematic eye shown in Figure 19-3. Get solution
5. Estimate the electric field strength at the center of the focused spot of Example 28-1. Get solution
6. A laser system, fixed on a geosynchronous satellite, uses a Nd:YAG laser that emits 1.06 μm radiation in a highly collimated beam of 5-μrad beam divergence.a. If the laser is 36,205 km above Earth, what is the minimum diameter of the laser-beam “footprint” on the surface of Earth?b. If the laser emits pulses of 200-MW power, what is the average electric field per pulse in the laser beam at Earth’s surface? Get solution
7. Personnel who work with high-power lasers or with unshielded laser beams must take measures to protect themselves from laser damage to the skin and eyes. Toward that end, nominal hazard zones (NHZ) for given lasers can be defined. A NHZ outlines the conical space within which the level of direct, reflected, or scattered radiation—during normal operation—exceeds the assigned levels of maximum permissible exposure (MPE). Exposure levels outside the conical region are below the designated MPE level. The conical region, with lip emanating from the laser, extends to a range RNHZ, with sides spreading at the full-angle beam divergence ϕ. The range for a non focused laser beam is given by ...where P is the laser power, ϕ is the beam divergence, MPE is the maximum permissible exposure in power/area, and d is the aperture diameter of the laser exit port.a. Draw a sketch of the NHZ (conical shape), labeling the extent of the cone, RNHZ and the full-angle beam divergence ϕ.b. Determine RNHZ for a continuous wave Nd:YAG laser (λ = 1.06 μm) of 50-W power, 3.0-mrad beam divergence, MPE of 5.1 × 10−3 W/cm2, a 10-s exposure, and an exit aperture diameter of 3.0 mm. Get solution
8. The range RNHZ (refer to problem 1) for a laser that directs its exiting laser beam immediately onto a lens is given by ...where RNHZ defines the extent of the cone emanating from the point of beam focus, f is the focal length of the lens, b is the diameter of the beam exiling the laser, P is the power of the laser, and MPE is the maximum permissible exposure.a. Draw a sketch of the NHZ (conical space) for this focused laser beam.b. Determine RNHZ for a continuous wave Nd:YAG laser of 50-W power, exit beam diameter of 5.0 mm, and capped by a lens of focal length 7.5 cm, if the MPE of this laser for an 8-hr exposure is 1.6 × 10−3 W/cm2.Problem 1Personnel who work with high-power lasers or with unshielded laser beams must take measures to protect themselves from laser damage to the skin and eyes. Toward that end, nominal hazard zones (NHZ) for given lasers can be defined. A NHZ outlines the conical space within which the level of direct, reflected, or scattered radiation—during normal operation—exceeds the assigned levels of maximum permissible exposure (MPE). Exposure levels outside the conical region are below the designated MPE level. The conical region, with lip emanating from the laser, extends to a range RNHZ, with sides spreading at the full-angle beam divergence ϕ. The range for a non focused laser beam is given by ...where P is the laser power, ϕ is the beam divergence, MPE is the maximum permissible exposure in power/area, and d is the aperture diameter of the laser exit port.a. Draw a sketch of the NHZ (conical shape), labeling the extent of the cone, RNHZ and the full-angle beam divergence ϕ.b. Determine RNHZ for a continuous wave Nd:YAG laser (λ = 1.06 μm) of 50-W power, 3.0-mrad beam divergence, MPE of 5.1 × 10−3 W/cm2, a 10-s exposure, and an exit aperture diameter of 3.0 mm. Get solution
9. Investigate the tuning of the signal and idler frequencies of an OPO using a PPLN crystal. In particular, find a PPLN spatial frequency KC that will produce a signal of wavelength 2400 nm when the pump is (a) an Nd:YAG laser and (b) a frequency-doubled Nd:YAG laser. Assume that the operating temperature is room temperature. (To solve this problem you will have to do some research. The free software program called SNLO, available from the Sandia National Laboratory web site, would prove very useful.) Get solution
10. Consider an OPO system pumped with Nd:YAG laser radiation. For a certain configuration, the signal beam is found to have a wavelength of 1500 nm.a. Find the wavelength of the idler beam.b. Find a cavity length d, near 1 m, that will allow both signal and idler to resonate by modeling the cavity as having two flat mirrors and ignoring the influence of the PPLN crystal on the cavity mode frequencies. That is, take the cavity mode frequencies to be given by vq = qc/(2d).c. Refine the calculation of part (b) by finding a cavity length near 1 m that will allow both the signal and idler to resonate, in a TEM00 mode, in a cavity with one flat mirror and one mirror of radius of curvature 2 m. In this case, the cavity mode frequencies are given by Eq. (27-67). Get solution
11. Consider a two-mirror cavity and take the reflectance of each mirror to be R = 0.97. Let resonant light of power 100 mW be incident into the cavity. Find the (one-way) power in the intracavity beam. Get solution
12. Who won the Nobel prizes for physics in 1997 and 2001. Summarize the work that led to the awards. Get solution
13. Who won the Nobel Prize for chemistry in 1999. Summarize the work that led to the award. Get solution
14. Summarize the contents of a journal article describing a femtosecond dye laser experimental setup. Get solution
15. Find the aperture size and position used in a real Kerr-lens, mode-locked, Ti:sapphire laser system. Get solution
16. a. Calculate the root-mean-square room-temperature speed of an oxygen molecule.b. Find the root-mean-square speed of an atom in a gas sample of rubidium at a temperature of 2 mK. Get solution
17. Estimate the amount of Doppler detuning δ (see Figure 28-3) that should be used to cool a gas sample of rubidium atoms at a temperature of 3 mK. Take the transition wavelength to be 800 nm. (Equation (4-44) might prove useful.) Get solution
18. After doing research, answer the following questions.a. What is an atom-interferometer?b. Why is there an interest in atom-interferometers? Get solution
19. After doing research, describe the nature of the trapping force that exists in the focal region of an optical tweezers arrangement. Get solution
20. After doing research, describe some experiments designed to study DNA with optical tweezers. Get solution
21. After doing research, describe how the tip deflection in an atomic force microscope can be measured by piezoresistive means. Get solution
22. Summarize the contents of a journal article detailing the use of a scanning probe microscope to image a biological sample. Get solution
23. Summarize the contents of a journal article detailing the use of a NSOM to measure the optical properties of a surface. Get solution
2. After doing some research, summarize the current state of the art with regard to the development of fibers through which excimer lasers can propagate with low loss. Get solution
3. Consider the medical procedure called posterior capsulotomy, illustrated in Figure 28-2 and discussed in the text surrounding that figure. Using the analytical tools developed in Chapter 27, choose a lens focal length, a beam-waist spot size at the lens, and a lens-to-cornea distance for use in the procedure. Be sure to respect the 17° convergence angle requirement indicated in the caption to Figure 28-2. For the system you design, calculate the beam-waist spot size at the focused spot, and the Rayleigh range parameter (z0) for the focused beam. Comment on the importance of the Rayleigh range in this design problem. It may be useful to refer to the schematic eye shown in Figure 19-3. Get solution
4. For the system designed in problem 1, find the irradiance at the center of the focused beam waist for an Nd:YAG laser of pulse energy 4 mJ and pulse width 1 ns. Compare the answer obtained with the estimate given in Example 28-1.Problem 1Consider the medical procedure called posterior capsulotomy, illustrated in Figure 28-2 and discussed in the text surrounding that figure. Using the analytical tools developed in Chapter 27, choose a lens focal length, a beam-waist spot size at the lens, and a lens-to-cornea distance for use in the procedure. Be sure to respect the 17° convergence angle requirement indicated in the caption to Figure 28-2. For the system you design, calculate the beam-waist spot size at the focused spot, and the Rayleigh range parameter (z0) for the focused beam. Comment on the importance of the Rayleigh range in this design problem. It may be useful to refer to the schematic eye shown in Figure 19-3. Get solution
5. Estimate the electric field strength at the center of the focused spot of Example 28-1. Get solution
6. A laser system, fixed on a geosynchronous satellite, uses a Nd:YAG laser that emits 1.06 μm radiation in a highly collimated beam of 5-μrad beam divergence.a. If the laser is 36,205 km above Earth, what is the minimum diameter of the laser-beam “footprint” on the surface of Earth?b. If the laser emits pulses of 200-MW power, what is the average electric field per pulse in the laser beam at Earth’s surface? Get solution
7. Personnel who work with high-power lasers or with unshielded laser beams must take measures to protect themselves from laser damage to the skin and eyes. Toward that end, nominal hazard zones (NHZ) for given lasers can be defined. A NHZ outlines the conical space within which the level of direct, reflected, or scattered radiation—during normal operation—exceeds the assigned levels of maximum permissible exposure (MPE). Exposure levels outside the conical region are below the designated MPE level. The conical region, with lip emanating from the laser, extends to a range RNHZ, with sides spreading at the full-angle beam divergence ϕ. The range for a non focused laser beam is given by ...where P is the laser power, ϕ is the beam divergence, MPE is the maximum permissible exposure in power/area, and d is the aperture diameter of the laser exit port.a. Draw a sketch of the NHZ (conical shape), labeling the extent of the cone, RNHZ and the full-angle beam divergence ϕ.b. Determine RNHZ for a continuous wave Nd:YAG laser (λ = 1.06 μm) of 50-W power, 3.0-mrad beam divergence, MPE of 5.1 × 10−3 W/cm2, a 10-s exposure, and an exit aperture diameter of 3.0 mm. Get solution
8. The range RNHZ (refer to problem 1) for a laser that directs its exiting laser beam immediately onto a lens is given by ...where RNHZ defines the extent of the cone emanating from the point of beam focus, f is the focal length of the lens, b is the diameter of the beam exiling the laser, P is the power of the laser, and MPE is the maximum permissible exposure.a. Draw a sketch of the NHZ (conical space) for this focused laser beam.b. Determine RNHZ for a continuous wave Nd:YAG laser of 50-W power, exit beam diameter of 5.0 mm, and capped by a lens of focal length 7.5 cm, if the MPE of this laser for an 8-hr exposure is 1.6 × 10−3 W/cm2.Problem 1Personnel who work with high-power lasers or with unshielded laser beams must take measures to protect themselves from laser damage to the skin and eyes. Toward that end, nominal hazard zones (NHZ) for given lasers can be defined. A NHZ outlines the conical space within which the level of direct, reflected, or scattered radiation—during normal operation—exceeds the assigned levels of maximum permissible exposure (MPE). Exposure levels outside the conical region are below the designated MPE level. The conical region, with lip emanating from the laser, extends to a range RNHZ, with sides spreading at the full-angle beam divergence ϕ. The range for a non focused laser beam is given by ...where P is the laser power, ϕ is the beam divergence, MPE is the maximum permissible exposure in power/area, and d is the aperture diameter of the laser exit port.a. Draw a sketch of the NHZ (conical shape), labeling the extent of the cone, RNHZ and the full-angle beam divergence ϕ.b. Determine RNHZ for a continuous wave Nd:YAG laser (λ = 1.06 μm) of 50-W power, 3.0-mrad beam divergence, MPE of 5.1 × 10−3 W/cm2, a 10-s exposure, and an exit aperture diameter of 3.0 mm. Get solution
9. Investigate the tuning of the signal and idler frequencies of an OPO using a PPLN crystal. In particular, find a PPLN spatial frequency KC that will produce a signal of wavelength 2400 nm when the pump is (a) an Nd:YAG laser and (b) a frequency-doubled Nd:YAG laser. Assume that the operating temperature is room temperature. (To solve this problem you will have to do some research. The free software program called SNLO, available from the Sandia National Laboratory web site, would prove very useful.) Get solution
10. Consider an OPO system pumped with Nd:YAG laser radiation. For a certain configuration, the signal beam is found to have a wavelength of 1500 nm.a. Find the wavelength of the idler beam.b. Find a cavity length d, near 1 m, that will allow both signal and idler to resonate by modeling the cavity as having two flat mirrors and ignoring the influence of the PPLN crystal on the cavity mode frequencies. That is, take the cavity mode frequencies to be given by vq = qc/(2d).c. Refine the calculation of part (b) by finding a cavity length near 1 m that will allow both the signal and idler to resonate, in a TEM00 mode, in a cavity with one flat mirror and one mirror of radius of curvature 2 m. In this case, the cavity mode frequencies are given by Eq. (27-67). Get solution
11. Consider a two-mirror cavity and take the reflectance of each mirror to be R = 0.97. Let resonant light of power 100 mW be incident into the cavity. Find the (one-way) power in the intracavity beam. Get solution
12. Who won the Nobel prizes for physics in 1997 and 2001. Summarize the work that led to the awards. Get solution
13. Who won the Nobel Prize for chemistry in 1999. Summarize the work that led to the award. Get solution
14. Summarize the contents of a journal article describing a femtosecond dye laser experimental setup. Get solution
15. Find the aperture size and position used in a real Kerr-lens, mode-locked, Ti:sapphire laser system. Get solution
16. a. Calculate the root-mean-square room-temperature speed of an oxygen molecule.b. Find the root-mean-square speed of an atom in a gas sample of rubidium at a temperature of 2 mK. Get solution
17. Estimate the amount of Doppler detuning δ (see Figure 28-3) that should be used to cool a gas sample of rubidium atoms at a temperature of 3 mK. Take the transition wavelength to be 800 nm. (Equation (4-44) might prove useful.) Get solution
18. After doing research, answer the following questions.a. What is an atom-interferometer?b. Why is there an interest in atom-interferometers? Get solution
19. After doing research, describe the nature of the trapping force that exists in the focal region of an optical tweezers arrangement. Get solution
20. After doing research, describe some experiments designed to study DNA with optical tweezers. Get solution
21. After doing research, describe how the tip deflection in an atomic force microscope can be measured by piezoresistive means. Get solution
22. Summarize the contents of a journal article detailing the use of a scanning probe microscope to image a biological sample. Get solution
23. Summarize the contents of a journal article detailing the use of a NSOM to measure the optical properties of a surface. Get solution