사용 현미경 및 구성 요소
1. 언제 사용 a 단안 현미경, 개발 그의 습관 의 관찰 함께 왼쪽 눈. 언제 관찰, 열림 둘 다 눈 at the same time, do not open one and close the other, because it is easy to fatigue. In order to train students to get used to observing with both eyes open at the same time, you can cut a rectangular piece of hard paper about 14cm long and 6cm wide, and dig a round hole near the left end with a diameter slightly smaller than the outer diameter of the upper end of the lens barrel. Put it on the upper part of the lens barrel, open both eyes at the same time when observing, use the right end of the paper to block the sight of the right eye, so that after a period of training, you can get used to opening both eyes at the same time, and then remove the paper.
2. The connection between the mirror arm and the mirror base of the straight microscope is a mechanical joint, which can be used to adjust the inclination of the mirror barrel for easy observation. The mirror arm should not be too backward, generally no more than 40 degree . 그러나, it is forbidden to use tilt joints when using temporary mounting slides for observation (when the lens barrel is tilted, the stage is also tilted, and the liquid on the slide glass is easy to flow out), especially when the slides contain acidic reagents, it is strictly forbidden to use to avoid Defile the mirror body.
3. 사용 of 접안렌즈 및 대물렌즈 렌즈
일반적으로, an eyepiece with a moderate magnification (10×) and an objective lens with the lowest magnification are used to start observation, and 점진적으로 use an objective lens with a higher magnification to find a magnification that meets the experimental requirements.
언제 변경 the objective lens, first observe with a low power lens and adjust to the correct working distance (the image is clearest). 만약 당신 사용 a 고배율 대물렌즈 렌즈 for 추가 관찰, 당신 해야 함 이동 the part of the object image that needs to be magnified to the center of the field of view before switching to a high-power objective lens (when the low-power objective lens is converted to a high-power objective lens for observation, the range of the object image in the field of view will be reduced a lot). the low magnification objective lens and the high magnification objective lens are basically parfocal (same as the high focus). 언제 사용 the low magnification objective lens to observe clearly, you should be able to see the object image with the high magnification objective lens, but the object image is not necessarily very clear. You can turn the fine focus screw to adjust adjust.
It is generally accepted that the upper limit of effective magnification with any objective lens is 1,000 times its numerical aperture and the lower limit is 250 times its numerical aperture. For example, if the numerical aperture of the 40× objective lens is 0.65, the upper and lower limits are: 1000×0.{% 7b8}} times and 250×0.65≈163 times, respectively. The upper limit of the effective magnification is called invalid magnification, which cannot improve the observation effect. If the magnification is lower than the lower limit, the human eye cannot distinguish it, which is not conducive to observation. general, the most practical magnification range is a number between 500 and 700 times the numerical aperture.
4. Use of oil immersion objective lens
언제 사용 기름 침수 대물렌즈, 일반적으로 do not use the same height focus. the same high-focus focusing is only applicable to the original objective lens of each microscope. It is a very favorable and convenient condition when using low-power and high-power objective lenses, but it is subject to certain restrictions when using oil-immersion objective lenses. 언제 관찰 표본 (슬라이드) 없음 a 덮개 유리, the accuracy of focusing at the same height is greater, but for specimens with a cover glass, be cautionful when using it, because the working distance of the oil immersion objective lens Very short, the height considered in the design and assembly is for standard thickness coverslips.
When using an oil immersion objective, only drip cedar oil on the slide. After the observation, it is necessary to clean it in time. If it is not done in time, the cedar oil will stick to dust, and the dust particles may wear the lens when wiping. The cedar oil will thicken and dry after being exposed to the air for a long time, making it difficult to wipe. Bad for the instrument. Wipe carefully and lightly. Wipe the front end of the oil-immersion objective lens once or twice with a dry lens tissue to remove most of the oil, then wipe it twice with a lens tissue wetted with xylene drops, and finally wipe it once with a dry lens tissue. The cedar oil on the specimen can be removed by the "paper pulling method" (that is, cover a small piece of lens cleaning paper on the cedar oil, then drop some xylene on the paper, and pull the paper out while it is wet. Clean, generally will not damage smear specimens without coverslips) Wipe clean. The lens cleaning paper should also be dustproof. Generally, before use, each page is cut into 8 small pieces and stored in a clean small petri dish, which is economical and convenient to use.
5. 방법 to 사용 집중 장치
①. 이유 for using concentrators
②. The height at which the condenser should be located during observation
When observing, to ensure the best observation effect, the focus of the condenser should just fall on the specimen. To achieve this condition, the height of the concentrator must be adjusted. When parallel light is used for illumination, the focal point of the condenser is about 1.25mm above the center of its upper lens plane. The height of the stage plane so that the focal point of light may fall on specimens placed on standard thickness slides. When using a glass slide that is thinner than the standard thickness to hold the specimen, the position of the condenser should be lowered accordingly, and when using a glass slide that is too thick, the focus of the light can only fall below the specimen, which is not conducive to fine observation.
③. 조정 콘덴서 및 대물렌즈 렌즈 사이
The so-called cooperation here is to make the numerical apertures of the condenser and the objective lens consistent, so as to perform finer observation better. If the numerical aperture of the condenser is lower than that of the objective lens, then part of the numerical aperture of the objective lens is wasted, thus failing to achieve its highest resolution. If the numerical aperture of the condenser is larger than the numerical aperture of the objective lens, on the one hand, the specified resolution of the objective lens cannot be improved, and on the other hand, the clarity of the object image will be reduced due to the too wide illumination beam. The operation method for the cooperation between the condenser and the objective lens is: after completing the lighting and focusing operations, take off the eyepiece and look directly into the lens barrel, close the iris diaphragm under the condenser to the minimum, and then slowly open it up. . Open until its aperture is just as large as the diameter of the field of view, and then press the eyepiece to observe. Every time the objective lens is converted, such cooperation operations must be carried out in sequence. The frame of the iris diaphragm of some condensers is engraved with a scale indicating the opening aperture, which can be matched according to the scale.
