Telescope

Today, microscopes are of great importance especially on the field of Biological Science. One of its major use is to determine the sizes of microorganisms which are of great importance in understanding certain biological phenomena. Getting the actual size of microscopic objects such as microorganisms using calibrated eyepiece micrometer is termed micrometer (Echoic, et. Al. , 2000). It is important for investigators across a number of disciplines. A biologist, for example, needs to know the exact size of two organisms to provide an intelligent comparison (I. E.Almoner). The intent of this activity is to create an awareness in proper handling techniques ND correct use of a microscope to students pursuing courses in the field of Biological Sciences. This activity is also intended to teach students microscope calibration techniques. II. Materials and Methods To able to obtain the exact measurement of a specimen, the ocular micrometer should be calibrated first. By doing so, the calibrat ion constant (C) is obtained. To get the calibration constant, a stage micrometer, an ocular micrometer and a microscope is used.The ocular micrometer was placed inside the ocular lens of the microscope and the stage micrometer on the stage. The field was adjusted so that a line in the ocular micrometer is superimposing a line in the stage micrometer. Once this was set, the number of divisions in both micrometers from the first superimposing lines to the next line that superimposed was counted. The number of divisions in the stage micrometer was divided by the divisions in the ocular micrometer. The quotient was multiplied by pm.The product obtained was the calibration constant. The calibration constant was determined in each of the objective lenses of the microscope. Once the ocular micrometer was calibrated, the pastimes were viewed and measured. The correct measurement was obtained by counting the ocular micrometer divisions occupied by the specimen and multiplying it by the cali bration constant of the objective lens used. The deviation between the measurement should only appear on the decimal places of the figure. Ill. Results and Discussion Table 1. Calibration Constant Under Different Microscope Objective Lenses Table 1. 0 shows the summary for the computed calibration constant under the high power objective (HOP) and the the low power objective (LOOP). Under the HOP, the umber of divisions in the ocular micrometer between the two superimposing lines is four while on the stage micrometer it is five. Dividing five by four, the value 1. 25 is obtained. This is not yet the calibration constant. The value 1. 25 should be multiplied by Imp to get the C.By doing so, we get 12. Pm as the C under the HOP. For the LOOP the recorded stage micrometer division is five while the ocular micrometer division is fifteen. Dividing five by fifteen we get the value 0. 3333. Multiplying this value by pm, we get a C of 3. Amp under the LOOP. The calibration constant differ en der different magnifications. Table 2. 0 Size Measurement of Amoeba through Calibrated Ocular Micrometer MOD* Size (MOD X ICQ Average Length HOP 61 203. Apron 203. 531 pm LOOP 16. 3 203. PRNG Width 15 49. 995 pm 49. 98 pm 4 pm *OMG)- Ocular Micrometer Divisions Since the ocular micrometer was already calibrated, the exact measurement of the specimen can now be obtained. A prepared slide of Amoeba is used as the first specimen. Two dimensions was measured in the specimen, the length and the width. For the length, the specimen occupies 61 MOD under the HOP and 16. 3 MOD under the LOOP. Multiplying the MOD by the C, we get the exact size of the specimen. Under the HOP, the exact length is 203. Pm while on the LOOP it is 203. Pm. By averaging we get 203. 31 pm as the exact length of the first specimen. Same process was done with the measurement of the width. Under the HOP, 15 MOD was occupied providing a measurement of 49. Pm. For the LOOP, four MOD was occupied providing a measurement of pm. By getting the average we get 49. Pm as the exact width of the specimen. Table 2. 1 Size Measurement of Radiogram through Calibrated Ocular Micrometer 101 336. 663 337. 067 27 337. Apron 6 86. Mom 86. Mom 6. 9 86. PRNG For the second specimen, a prepared slide of Radiogram was used.The measurement procedure was Just the same to that of the Amoeba (specimen 1). For the length, under the HOP, the Radiogram occupies 101 MOD giving a size of 336. Pm. Under the LOOP it occupies 27 MOD equivalent to a size of 337. Pm. By averaging, we get 337. Pm for the length of the specimen. For the width, the specimen occupies 26 MOD under the HOP which is equivalent to 86. Pm. Under the LOOP, 6. 9 MOD was occupied giving a size of 86. Pm. We get 86. Pm for the width of the specimen.