Find the odd word in each list.
- signal, signalled, signaling, sign
- illumination, enlightenment, inspiration, depression
- motion, movement, change, description
16. Discuss in pairs: “What are the quantities and units used in photometry?” use the table. Start your discussion with this introduction…
· They are basically the same as …and have names...
· A few additional units have been introduced to deal with the amount of...
· The symbols used are identical to …
| QUANTITY | RADIOMETRIC | PHOTOMETRIC |
| power | watt (W) | lumen (lm) |
| power per unit area | W/m2 | lm/m2 = lux (lx) |
| power per unit solid angle | W/sr | lm/sr = candela (cd) |
| power per area per solid angle | W/m2-sr | lm/m2-sr = cd/m2 = nit |
17. Choose the appropriate pronoun (something; someone, somebody, anything; anyone, anybody).
1. There isvery pleasant in her voice.
2. Doesof you want to speak on this topic?
3. We must askto show us the way to the post-office.
4. We didn't meetnear the river.
5. The tourists spoke simple English andof us could understand what they said.
6. If you need, ask me, please.
7. He was never angry with.
8 got up and saidbut he spoke so silently that we could hardly hear .
9 writes it very witty.
10. Will help me?
11. Wouldn't you tell about your future plans.
12. She doesn't know of them.
13. The children can do useful in the garden.
Be ready to speak on the topic “Photometry and Radiometry”.
19.Complete the sentences using the given words:
| important categorized difference hand techniques |
1. Light is measured using the of photometry, which deal with brightness as perceived by the human eye, rather than absolute power.
2. Radiometry is in astronomy, especially radio astronomy, and is important for Earth remote sensing.
3. The measurement techniques as radiometry in optics are called photometry in some astronomical applications, contrary to the optics usage of the term.
4. The only real between radiometry and photometry is that radiometry includes the entire optical radiation spectrum, while photometry is limited to the visible spectrum as defined by the response of the eye.
5. Photometry is more difficult to understand, primarily because of the arcane terminology, but is fairly easy to do, because of the limited wavelength range. Radiometry, on the other is conceptually somewhat simpler, but is far more difficult to actually do.
Unit 18
VISION AND IMAGE SENSORS
1. Practice reading words:
Vision, inaccessible, dimensions, satellites, diagnosis, distinguished, sharpness, readout, shift, fragility, smear, aliasing, exposure,Charge-Coupled.
How can be explained the terms “vision”, “image”? What are the spheres or their usage? Try to describe with your own words the process of image formation.
Read and translate the text A
TEXT A
Image Formation
Vision is the act of seeing, a human capability derived from the combination of the image forming optical system of the eye, the array of light sensitive receptors in the retina of the eye, and the information processing capacity of the retina and human brain. Applications for instruments with a similar ability to sense a scene include broadcast television, monitoring industrial processes, quality control during manufacture, viewing inaccessible or hazardous places, aiding medical diagnosis, and remote sensing from satellites and space probes, to name but a few. The human eye is a familiar imaging system, highly optimized to aid survival under the naturally occurring range of illumination conditions.
The machine vision optical system (Fig.18.1) has the tasks of matching the required field of view to the dimensions of the sensor and gathering sufficient light to achieve a sensor signal that has adequate signal-to-noise ratio (SNR) while maintaining the image sharpness required by the application.
Figure 18.1. Machine vision optical system
Resolutions of area sensors are sometimes specified by manufacturers as the maximum number of horizontal TV lines that can be distinguished. This value may be obtained from measurements of the visibility of a test chart (EIA test pattern), or it may simply be the number of horizontal pixels divided by 1.33, in the case of a monochrome sensor. Machine vision characteristics depend on the type of image sensor employed and the modifying effects of additional components such as image intensifiers or optical fiber scopes.
Дата: 2016-10-02, просмотров: 167.
