94 Keysight 81618A/9A and Keysight 81620B/3B/4B/6B/8B Optical Heads User’s Guide5 Cleaning InformationAdditional Cleaning EquipmentSome Cleaning Procedures need the following equipment, which is notrequired to clean each instrument:• Microscope with a magnification range about 50X up to 300X• Ultrasonic bath• Warm water and liquid soap• Premoistened cleaning wipes• Polymer film• Infrared Sensor CardMicroscope with a magnification range about 50X up to 300XA microscope can be found in most photography stores, or can beobtained through or specialist mail order companies. Special fiber-scopesare available from suppliers of splicing equipment.Ideally, the light source on your microscope should be very flexible. Thiswill allow you to examine your device closely and from different angles.A microscope helps you to estimate the type and degree of dirt on yourdevice. You can use a microscope to choose an appropriate cleaningmethod, and then to examine the results. You can also use yourmicroscope to judge whether your optical device (such as a connector) isseverely scratched and is, therefore, causing inaccurate measurements.Ultrasonic bathUltrasonic baths are also available from photography or laboratorysuppliers or specialist mail order companies.An ultrasonic bath will gently remove fat and other stubborn dirt from youroptical devices. This helps increase the life span of the optical devices.Only use isopropyl alcohol in your ultrasonic bath, as other solvents maycause damage.Warm water and liquid soapOnly use water if you are sure that there is no other way of cleaning youroptical device without causing corrosion or damage. Do not use hot water,as this may cause mechanical stress, which can damage your opticaldevice.Ensure that your liquid soap has no abrasive properties or perfume in it.You should also avoid normal washing up liquid, as it can cover yourdevice in an iridescent film after it has been air dried.