Thermometer development at home and abroad

1. Thermometer in the domestic development of the current situation (1) the development of temperature sensors Temperature sensors are used in a wide range, a large number, the first of a variety of sensors, and its development has gone through the following three stages: ① traditional discrete temperature sensors (including sensitive elements) - thermocouple sensors, the main thing is to be able to carry out the non-electricity and the conversion between electricity. ① Traditional discrete temperature sensors (including sensitive elements - thermocouple sensors, mainly capable of non-electrical and electrical conversion. ② analog integrated temperature sensor/controller. Integrated sensors are made using a silicon semiconductor integration process, and are therefore also called silicon sensors or monolithic integrated temperature sensors. Intelligent temperature sensor. It is the crystallization of microelectronics technology, computer technology and automatic test technology (ATE_). Intelligent temperature sensor contains temperature sensors, A/D sensors, signal processors, memory (or registers) and interface circuits.

2. The development of thermometers in foreign countries

The history of temperature measurement can be traced back to the l6th century. At that time, Saatorio used the principle of thermal expansion of air to produce the first thermometer to measure the temperature of the oral cavity. At the beginning of this century, mercury began to be used to make thermometers, which are widely used in clinical practice today. According to Ebstein's report in 1928, at that time, in addition to measuring the temperature of the oral cavity and the axilla, it was also possible to measure the rectum, the neck, the roots of the thighs, the external ear, the vaginal temperature and the urine temperature. These were realized using the principle that the temperature of the skin being measured was equal to the temperature of the mercury accumulated in the glass bulb. Mercury thermometers are widely used because of their ease of use and accuracy. Coupled with the fact that the method of temperature measurement and its structure are mature, leaving little room for improvement, people have lost confidence in its research and little progress has been made so far. Due to the inconvenience of monitoring body temperature with mercury thermometers and the serious contamination of mercury, etc., in order to correctly measure the local temperature, it has recently prompted the development of a variety of different temperature measuring instruments and temperature measuring methods. Only because the clinical temperature measurement method has not changed much, the electronic thermometer popularized in recent years can not obtain more physiological information, and the accuracy is not much improved, compared with the mercury thermometer is still a high precision, cheap, easy to use temperature measurement instruments. Therefore, blindly use the electronic thermometer to replace the mercury thermometer is not necessarily appropriate, if only pay attention to the mercury contamination problem, must use the electronic thermometer to replace the mercury thermometer is not sufficient reason. In spite of this, many hospitals have adopted electronic thermometers, and the use of other electronic devices to measure body temperature is becoming increasingly popular. This fact at least suggests that the performance of electronic thermometers is approaching that of mercury thermometers. As a result of the use of electronic instruments, new methods of temperature measurement have emerged, but in the current situation, comparable to the mercury thermometer, a more complete temperature measurement instruments have not yet been introduced. Therefore, compared with the history of the mercury thermometer, it can be said that the electronic thermometer as the first of the modern temperature measurement instruments are still stuck in the 19th century level, in view of the traditional mercury thermometer mercury contamination and its inconvenience to carry easy to break, especially the measurement time is too long and other shortcomings, the subject of the problem of designing a new type of intelligent electronic thermometer. It has significant advantages over the traditional mercury thermometer in terms of stability and response time, and the accuracy requirements can also be comparable to the traditional mercury thermometer.