All the truth about microscopes
СОДЕРЖАНИЕ
Введение……………………………………………………………………….4
1. Lesson 1. Laser Rangefinder………………………………………………...5
2. Lesson 2. All the Truth about Microscopes………………………………….9
3. Lesson 3. Digital Signal Processing………………………………………...13
4. Lesson 4. What Is a Sensor?………………………………………………...18
5. Lesson 5. Pressure Sensors………………………………………………….22
6. Lesson 6. Microcontrollers………………………………………………….26
7. Lesson 7. The Science of Measurement…………………………………….31
8. Lesson 8. Leveling the Level……………………………………………….35
Final Test………………………………………………………………………40
Библиографический список………………………………………………….44
ВВЕДЕНИЕ
Данные методические указания предназначены для использования на практических занятиях по английскому языку и для самостоятельной работы студентов I и II курса специальности «Приборы точной механики» факультета «ТАМПТ» дневной формы обучения.
Основной целью методических указаний является совершенствование языковых знаний и коммуникативных умений студентов благодаря активизации использования лексики (как общего характера, так и профессиональной направленности) при переводе технических текстов и написании аннотаций, а также благодаря развитию умений принимать участие в беседе (как в академической, так и в профессиональной среде).
Данные методические указания состоят из восьми уроков, каждый из которых включает тексты для чтения и перевода, обсуждения и составления аннотаций, систему упражнений для предтекстового, текстового и послетекстового этапов работы, которые направлены на реализацию задач, расширение словарного запаса и совершенствование навыков практического владения английским языком. Цикл уроков завершает итоговый тест, который состоит из двух вариантов и направлен на проверку усвоения информации и лексики, содержащейся во всех восьми уроках данных методических указаний.
LESSON 1
LASER RANGEFINDER
Lexical units:
laser rangefinder – лазерный дальномер
target – цель, объект
high precision – (здесь) точный
sub-millimeter measurements – измерения очень малых единиц длины
triangulation – тригонометрическая съёмка
rise time – время нарастания
fall time – время спада
reading – показание прибора
to vanish – исчезать
gradient – отклонение
time-of-flight – «время пролёта»
single-face – единичный
to merge – поглощать, соединять
archery – стрельба из лука
stock management – управление запасами
real estate – недвижимость
tape measure – рулетка
TEXT
A laser rangefinder is a device which uses a laser beam to determine the distance to an object. The most common form of a laser rangefinder operates on the time of flight principle by sending a laser pulse in a narrow beam towards the object and measuring the time taken by the pulse to be reflected off the target and returned to the sender. Due to the high speed of light, this technique is not appropriate for high precision sub-millimeter measurements, where triangulation and other techniques are often used.
The precision of the instrument is determined by the rise or fall time of the laser pulse and the speed of the receiver. One that uses very sharp laser pulses and has a very fast detector can range an object to within a few millimeters.
Some of the laser light might reflect off leaves or branches which are closer than the object, giving an early return and a reading which is too low. Alternatively, over distances longer than 1,200 ft (365 m), the target may simply vanish into a mirage, caused by temperature gradients in the air in proximity to the heated desert bending the laser light. All these effects have to be taken into account.
Nowadays laser rangefinders are used extensively in 3-D object recognition and 3-D object modelling. This technology constitutes the heart of the so-called time-of-flight 3D scanners. (This measures the time taken for a light pulse to travel to the target and back. With the speed of light known, and an accurate measurement of the time taken, the distance can be calculated.) In contrast to different military instruments, laser rangefinders offer high-precision scanning abilities, with either single-face or 360-degree scanning modes.
A number of algorithms have been developed to merge the range data retrieved from multiple angles of a single object to produce complete 3-D models with as little error as possible. One of the advantages that laser rangefinders offer over other methods of computer vision is that the computer does not need to correlate features from two images to determine depth information as in stereoscopic methods.
Special laser rangefinders are used in forestry. These devices have anti-leaf filter and are working with reflector. Laser beam only reflects from this reflector, and so exact distance measurement is guaranteed. For example, laser rangefinders with anti-leaf filter are used for forest inventories.
Laser rangefinders may be effectively used in various sports that require precision distance measurement, such as golf, hunting, and archery. An important application is the use of laser rangefinder technology during the automation of stock management systems and production processes in steel industry.
Laser rangefinders are also used in several industries like construction, renovation and real estate as an alternative to a tape measure. Whereas with a tape measure one would need two people to measure a large object like a room with a straight run with no obstructions to stretch the tape, with a laser measuring tool the job can be completed by one operator with just a line of sight. Laser measuring tools typically include the ability to produce some simple calculations such as the area or volume of a room.
Comprehension
Exercise 1.True or false?
1) The precision of the instrument is determined by the rise or fall time of the laser pulse only.
2) Special laser rangefinders are used in various sports, as football, curling, and weight lifting.
3) Laser rangefinders are used extensively in 3-D object recognition.
4) You only need one operator to measure a large object with a laser rangefinder.
5) The most common form of laser rangefinders operates on the flight-in-time principle.
6) Triangulation is often used for high precision sub-millimeter measurements.
7) Some laser measuring tools include the ability to produce simple calculations.
8) The computer does not need to correlate features from two images to determine depth information.
9) Sometimes temperature gradients in the air in proximity to the heated desert cause a mirage.
10) A laser rangefinder determines the distance to different objects.
Exercise 2.Complete the sentences using the correct words from the text:
1) In contrast to different … instruments, laser rangefinders offer … … abilities.
2) An important … is the use of laser … technology during the automation of stock … systems.
3) Over distances … than 365 m, the … may simply vanish into a ….
4) Due to the high speed of …, this technique is not … for high precision … measurements.
5) The … can be calculated with the … of light known, and an accurate … of the time taken.
6) With a … measure one would need … people to measure a large … like a room.
7) Laser rangefinders are used … in … object recognition and … object ….
8) The most … form of a laser rangefinder operates on the … of … principle.
Vocabulary
Exercise 3.Give the English or Russian equivalents for the following word combinations:
Распознавание объектов; laser measuring tools; время спада импульса; with as little error as possible; вследствие высокой скорости света; to reflect off leaves or branches; производственные процессы в стальной промышленности; to require precision distance measurement; на расстоянии более 365 метров; very sharp laser pulses.
Exercise 4.Match the words with their meanings:
| 1) tool | a) accuracy; freedom from error |
| 2) measurements | b) implement or apparatus used in performing an action, especially for scientific work |
| 3) precision | c) trade or manufacture |
| 4) instrument | d) mechanism for emitting electromagnetic radiation via the process of stimulated emission |
| 5) industry | e) figures of measurement as shown on a dial, scale, etc |
| 6) mode | f) device that can be used to produce or achieve something, but that is not consumed in the process |
| 7) laser | g) figures about length, breadth, depth, etc |
| 8) readings | h) way in which something is done |
Exercise 5.Translate from Russian into English:
1) Как известно, лазерный дальномер – это устройство, состоящее из импульсного лазера и детектора излучения. 2) Способность электромагнитного излучения распространяться с постоянной скоростью даёт возможность определить расстояние до объекта. 3) Сегодня технологии лазерного дальномера широко применяются при производстве высококачественных стальных и медных изделий. 4) Если бы лазерный луч не применялся в этом приборе, его показания не были бы такими точными. 5) Не каждый может в одиночку измерить объём и площадь большого помещения с помощью рулетки. 6) Тригонометрическая съёмка применяется многими исследовательскими организациями для измерения очень малых единиц длины. 7) Измеряя время, которое затрачивает луч на путь до отражателя и обратно, и зная значение скорости света, можно рассчитать расстояние между лазером и отражающим объектом. 8) Технологии распознавания и моделирования трёхмерных объектов постоянно развиваются и никогда не стоят на месте. 9) Если лазерные измерительные приборы не имеют программ для ведения простых математических расчётов, спрос на такие приборы падает. 10) В пустыне миражи появляются вследствие отклонений температуры воздуха на расстоянии трёх метров от земли.
Exercise 6.Make up the summary of the text and write its annotation.
Discussion
Exercise 7.Work in pairs or in small groups. Share in the discussion. Use the following questions as prompts:
1) What is a laser rangefinder?
2) Could you describe the most common principle of its work?
3) What conditions are necessary to range any object within a few millimeters?
4) Could you name the effects to be taken into account concerning the work of a laser rangefinder?
5) Could you give the characteristic to the time-of-flight technology?
6) What is the advantage of a laser rangefinder as compared to any stereoscopic methods?
7) How can a laser rangefinder be used in forestry? And in sports?
8) Why can we consider a tape measure an out-of-date and inconvenient tool nowadays?
LESSON 2
ALL THE TRUTH ABOUT MICROSCOPES
Lexical units:
scanning probe microscope – сканирующий зондовый микроскоп
to magnify – увеличивать с помощью микроскопа
magnification – увеличение
transmitted light – проходящий свет
condenser lens – конденсорная линза
eyepiece – окуляр
objective turret – турель объектива
stage – предметный столик
focus wheel – винт микроскопа
comparison microscope – сравнительный микроскоп
inverted microscope – инвертированный микроскоп
to be a household name – быть на слухý
in essence – по сути
transillumination – трансиллюминация, просвечивание
incident light – падающий свет
charge-coupled device camera –
камера с зарядовой связью (для сканирования)
to omit – не включать, пропускать
specimen – образец
particle beam – пучок частиц
resolving power – разрешающая способность
failure analysis – анализ отказов/повреждений
raster scan – растровое сканирование
piezoelectric actuator – пьезоэлектрический регулятор
TEXT
A microscope is an instrument to see objects too small for the naked eye. Thereafter, the science of investigating small objects using such an instrument is called microscopy.
Of course, you may guess that there are many types of microscopes. The most common and first to be invented (in 1590) is the optical microscope which uses light to image the sample. Other major types of microscopes are the electron microscope and the scanning probe microscope.
The optical microscope, often referred to as the "light microscope," uses visible light and a system of lenses to magnify images of small samples. Basic optical microscopes can be very simple, although there are many complex designs which aim to improve resolution and sample contrast. Historically optical microscopes were easy to develop and are popular because they use visible light, so the sample can be directly observed by eye.
All modern optical microscopes designed for viewing samples by transmitted light share the same basic components of the light path, listed here in the order the light travels through them: 1) light source, usually a mirror; 2) diaphragm and condenser lens; 3) objective; 4) ocular lens (eyepiece). In addition the vast majority of microscopes have the same structural components: objective turret to hold multiple objective lenses, stage to hold the sample, and focus wheel to move the stage.
There are many variants of the basic compound optical microscope design for specialized purposes. Some of these are stereo microscope, comparison microscope, inverted microscope, etc. But we’d better pay attention to the USB microscope and to the digital microscope as they are now household names just everywhere.
A USB microscope is a low-powered digital microscope which is connected to a computer, normally via a USB port. They are widely commercially available. In essence, USB microscopes are a webcam with a high-powered macro lens and generally do not use transillumination but rely on incident light instead. As the camera attaches directly to the USB port of a computer, eyepieces are not required and the images are shown directly on the monitor. They offer modest magnifications (up to about 200×) without the need to use eyepieces at very low cost, although lack of illumination optics limits their use. USB microscopes are most useful when examining flat objects such as coins or banknotes. They can be used even in the field, attached to a laptop computer.
A digital microscope is a variation of a traditional optical microscope that uses optics and a charge-coupled device (CCD) camera to output a digital image to a monitor, sometimes by means of software running on a computer. A digital microscope differs from an optical microscope in that there is no provision to observe the sample directly through an eyepiece. Since the optical image is projected directly on the CCD camera, the entire system is designed for the monitor image. The optics for the human eye are omitted.
An electron microscope is a type of microscope that produces an electronically-magnified image of a specimen for detailed observation. The electron microscope uses a particle beam of electrons to illuminate the specimen and create a magnified image of it. The microscope has a greater resolving power than an optical microscope, because it uses electrons that have wavelengths about 100,000 times shorter than visible light (photons), and can achieve magnifications of up to 2,000,000x, whereas light microscopes are limited to 2,000x magnification. Industrially, the electron microscope is primarily used for quality control and failure analysis in semiconductor device fabrication.
With the use of scanning probe microscopes, an image of the surface is obtained by mechanically moving the probe in a raster scan of the specimen. The resolution varies somewhat from technique to technique, but some probe techniques reach a rather impressive atomic resolution. They owe this largely to the ability of piezoelectric actuators to execute motions with accuracy at the atomic level.
Comprehension
Exercise 1.True or false?
1) The optical microscope is often referred to as the “light microscope.”
2) A microscope is an instrument to see objects in the outer space.
3) The optical microscope was invented in 1950.
4) A USB microscope is a high-powered digital microscope.
5) The electron microscope uses electrons to illuminate the specimen.
6) The optics for the human eye are omitted in digital microscopes.
7) Optical microscopes may be connected to a laptop via USB ports even in the field.
8) At first the light travels through an ocular lens and then through a mirror.
9) Piezoelectric actuators are able to execute motions with accuracy at the atomic level.
10) An electron microscope offers rather modest magnifications.
Exercise 2.Complete the sentences using the correct words from the text:
1) A … microscope differs from an … microscope in that there is no provision to observe the sample directly through an ….
2) The optical microscope uses … light and a system of … to magnify images of small ….
3) USB … are most useful when … flat objects such as … or banknotes.
4) The … microscope has a greater … power than an … microscope.
5) It uses … that have … about 100,000 times shorter than visible ….
6) Optical microscopes can have many … designs which … to improve … and sample contrast.
7) … of illumination optics … the use of … microscopes.
8) As the … attaches directly to the … … of a computer, … are not required.
Vocabulary
Exercise 3.Give the English or Russian equivalents for the following word combinations:
Анализ повреждений; to observe the sample directly through an eyepiece; постоянно быть на слуху; objective turret to hold multiple objective lenses; использовать свет для создания изображения образца; semiconductor device fabrication; маломощный цифровой микроскоп; basic components of the light path; веб-камера с макролинзами большой мощности; to be useful when examining flat objects.
Exercise 4.Match the words with their meanings:
| 1) USB | a) electronic light sensor used in digital cameras |
| 2) raster scan | b) ability to do or act |
| 3) charge-coupled device | c) a point toward which light rays are made to converge |
| 4) focus | d) rectangular pattern of image capture and reconstruction in television |
| 5) power | e) piece of glass or substance like glass with one or both sides curved |
| 6) design | f) one of a number taken to show what the rest is like |
| 7) lens | g) specification to establish communication between devices and a PC |
| 8) specimen | h) drawing or outline from which something may be made |
Exercise 5.Translate from Russian into English:
1) Глаз каждого человека представляет собой естественную оптическую систему, которая характеризуется определённым разрешением. 2) Сканирующий зондовый микроскоп позволяет регистрировать взаимодействие зонда с отдельными атомами и молекулами. 3) Создание изображений высокого разрешения было бы невозможно, если бы учёные не создали электронный микроскоп. 4) Для получения изображения в электронном микроскопе используются специальные магнитные линзы, которые управляют движением электронов при помощи магнитного поля. 5) Оптическая система микроскопа состоит из объектива и окуляра, которые закреплены в подвижном тубусе, расположенном на металлическом основании. 6) Большинство стереомикроскопов дает меньшее увеличение, чем современные оптические микроскопы, однако имеет большее фокусное расстояние, что позволяет рассматривать крупные объекты. 7) Разрешающей способностью микроскопа называется его способность выдавать чёткое раздельное изображение двух близко расположенных точек объекта. 8) Если бы мы не забыли наш ноутбук, мы бы смогли поучаствовать в практическом занятии с USB-микроскопом в лаборатории университета. 9) Под микроскопией мы понимаем совокупность технологий изготовления и практического применения микроскопов. 10) Растровое изображение – это прямоугольная сетка пикселей или точек цветов на компьютерном мониторе, бумаге и других устройствах и материалах.
Exercise 6.Make up the summary of the text and write its annotation.
Discussion
Exercise 7.Work in pairs or in small groups. Share in the discussion. Use the following questions as prompts:
1) Could you give any definitions to the terms microscope and microscopy?
2) Could you name three major types of microscopes?
3) What is the secret of popularity of the optical microscope?
4) What are the general components of all optical microscopes?
5) Would you be so kind as to state the most popular variants of optical microscope design?
6) How can you describe the essence of a USB microscope?
7) Where can we find a CCD camera? And what are its functions here?
8) Why does the electron microscope have a greater resolving power than an optical microscope?
9) Could you describe a scanning probe microscope?
LESSON 3