No book on problems can claim to exhaust the variety in the limited space. For simplicity, the spectral profile is assumed to be rectangular. Chapter 1 is devoted to the methods of Mathematical physics and covers such topics which are relevant to subsequent chapters. If all the photons emitted by the pump are absorbed by the crystal and used for the lasing process, calculate the maximum power output. %���� Laser light is usually spatially coherent, which means that the light either is emitted in a narrow, low-divergence beam, or can be converted into one with the help of optical components such as lenses. There is a broad range of materials that can be cut with a laser: wood, plastic, cardboard, textile... Laser cutting works by directing the output of a high-power laser through optics. A Q-switched laser emits pulses of 10µJ of duration 1 ns. 2. %PDF-1.5 Calculate the number of longitudinal modes that can oscillate in this cavity. The maximum output power is defined by stream The length of the cavity is equal to 1 m. 1. What is the rate of repetition of the pulses emitted by a mode-locked laser? ^ S��S�r�Ԯ�۶�U=$��^�������6�i���\�h�3���ǈ���?% /Filter/FlateDecode In a ring lasercavity, the beam passes through the medium only once each turn. Calculate the gap in frequency between two longitudinal modes in a linear cavity whose optic length, L, =300 mm. Question. The solution for non … ���.P��Z1j�������Ծ�܃��Y�4��b��� � �E�>"�e1�[b�M�����#"^�+��3JD��-���u.qUg�{*��^rz��N�~Z�����ٌG�)s�����r� /Filter/FlateDecode The frequency is therefore equal to. laser, concentrated on a very small area, in order to cut or engrave a material. 1. Calculate the energy of each pulse. The linear cavity is 30 cm long. CO2 has a bandwidth equal to x��͎� ��} There are no other energy levels nearby. stream Solution of Problem 4.12 Problem 4.13 A laser emitting at 0=850nm has a gain spectral width of = 32 nm and a peak gain of g(0) 50/cm , Plot g() equation 4.41. An one milliwatt He-Ne laser is highly intense than the sun intensity. fronts in recent years. A mode-locked laser emits an average power P equal to 1 W. The rate of repetition of the pulses from this laser is equal to 100 MHz. Calculate the peak power of the pulses. As the gap in frequency is given by the above formula, the distance that the cavity mirror must be moved is equal to: It is possible to make this fine adjustment by using a piezoelectric actuator. where k is a large integer. endobj TYPES OF LASERS 301 570-640 nm (rhodamine 6G) and many others. . ����rh�c��6��Ĩo�jl�4��n����;�]`��!��bH�g�ȳD�t��zo���KP�c�r2��y��i5�7�ނBV4��Lko)Q����H��җ����ܳ#8Jv�B=�kv�]�q ~�iH�����}P?�م��.M 峩�b�Q,�J��t@0 Suppose when two photons each of amplitude are in phase with other, then young’s principle of superposition, the resultant amplitude of two photons is 2 and the intensity is 4 . Calculate the number of longitudinal modes that can oscillate in this cavity. It is also widely used in industrial production and processing. xڝ�wTT��Ͻwz��0�z�.0��. /N 3 endstream �=��&�[�L�B�F��;���la��]�B�i3֏��9!�hcYD�ٿ�6��Ю�5H��6����h
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