Laser Optics - Pockels Cells: An Overview,Laser optics is a branch of optics that deals with the study of the behavior of light in laser systems. It involves the use of various optical components such as lenses, mirrors, prisms, and filters to manipulate the properties of laser light. One of the most important components in laser optics is the Pockels cell, which is used to control the polarization of laser light. In this article, we will discuss the mainstream models of laser optics - Pockels cells.,What is a Pockels Cell?,A Pockels cell is an electro-optic device that is used to control the polarization of laser light. It consists of a crystal that exhibits the Pockels effect, which is the change in the refractive index of a material in response to an applied electric field. When a voltage is applied to the crystal, the refractive index changes, which causes a rotation of the polarization of the incident laser light. By adjusting the voltage applied to the crystal, the polarization of the laser light can be controlled.,The Pockels effect was discovered by Friedrich Pockels in 1893. Since then, Pockels cells have been widely used in laser optics for a variety of applications, including Q-switching, mode locking, and pulse picking.,Mainstream Models of Pockels Cells,There are several mainstream models of Pockels cells, each with its own advantages and disadvantages. The most common models are the KD*P (potassium dihydrogen phosphate) and BBO (beta-barium borate) Pockels cells.,KD*P Pockels Cells,KD*P Pockels cells are the most widely used type of Pockels cell. They are made from a crystal of potassium dihydrogen phosphate (KH2PO4) that has been doped with potassium deuterium phosphate (KD2PO4). The crystal is cut into a specific orientation that allows it to exhibit the Pockels effect.,KD*P Pockels cells have several advantages over other types of Pockels cells. They have a high electro-optic coefficient, which means that they require a lower voltage to achieve the same polarization rotation as other types of Pockels cells. They also have a high damage threshold, which makes them suitable for use in high-power laser systems.,However, KD*P Pockels cells also have some disadvantages. They are sensitive to temperature changes, which can cause the crystal to crack or break. They also have a limited spectral range, which means that they are not suitable for use with lasers that operate outside of their spectral range.,BBO Pockels Cells,BBO Pockels cells are made from a crystal of beta-barium borate (β-BaB2O4). Like KD*P Pockels cells, they are cut into a specific orientation that allows them to exhibit the Pockels effect.,BBO Pockels cells have several advantages over KD*P Pockels cells. They have a wider spectral range, which makes them suitable for use with lasers that operate outside of the spectral range of KD*P Pockels cells. They are also less sensitive to temperature changes, which makes them more reliable in high-temperature environments.,However, BBO Pockels cells also have some disadvantages. They have a lower electro-optic coefficient than KD*P Pockels cells, which means that they require a higher voltage to achieve the same polarization rotation. They also have a lower damage threshold, which makes them less suitable for use in high-power laser systems.,Other Types of Pockels Cells,In addition to KD*P and BBO Pockels cells, there are several other types of Pockels cells that are used in laser optics. These include LiNbO3 (lithium niobate), LiTaO3 (lithium tantalate), and KTP (potassium titanyl phosphate) Pockels cells.,LiNbO3 and LiTaO3 Pockels cells are made from crystals of lithium niobate and lithium tantalate, respectively. They have a high electro-optic coefficient and a wide spectral range, which makes them suitable for use in a variety of laser systems. However, they are also sensitive to temperature changes and have a lower damage threshold than KD*P Pockels cells.,KTP Pockels cells are made from a crystal of potassium titanyl phosphate (KTiOPO4). They have a high damage threshold and a wide spectral range, which makes them suitable for use in high-power laser systems. However, they also have a lower electro-optic coefficient than KD*P Pockels cells, which means that they require a higher voltage to achieve the same polarization rotation.,Conclusion,Pockels cells are an important component in laser optics that are used to control the polarization of laser light. There are several mainstream models of Pockels cells, each with its own advantages and disadvantages. The most common models are the KD*P and BBO Pockels cells, which are widely used in a variety of laser systems. Other types of Pockels cells, such as LiNbO3, LiTaO3, and KTP Pockels cells, are also used in laser optics for specific applications.