閾波長度 的英文怎麼說
中文拼音 [yùbōzhǎngdù]
閾波長度
英文
threshold wave length- 閾 : 名詞1. [書面語] (門坎兒) threshold; doorsill2. (界限; 范圍) threshold
- 波 : Ⅰ名詞1 (波浪) wave 2 [物理學] (振動傳播的過程) wave 3 (意外變化) an unexpected turn of even...
- 長 : 長Ⅰ形容詞1 (年紀較大) older; elder; senior 2 (排行最大) eldest; oldest Ⅱ名詞(領導人) chief;...
- 度 : 度動詞[書面語] (推測; 估計) surmise; estimate
- 長度 : length; longitude; size; extent; footage
-
The second one : we studied the effect of temperature on performance of lds. it was found that threshold current increase exponentially outpower and slope efficiency decrease parabola and exponentially respectively. coefficient of temperature shift is 0. 24 / k, wheras characteristic temperature also decrease with rise of temperature
研究了溫度對激光器各參數的影響,隨著溫度的增加,閾值電流呈指數增加,輸出功率和斜率效率分別呈拋物線和指數關系遞減,同時特徵溫度也減少,波長隨溫度的漂移系數為0 . 24nm ,並且總結了一些溫度和結構設計方面的關系。In this paper, the contrast of original image is enhanced by nonlinear transformation based on the characteristics of grain image ; after comparing several methods of threshold segmentation and analyzing their performance and applicability on grain image, the adaptive threshold segmentation based on gradient image is presented ; the noise of binary image is reduced with morphological filter, the hollow in binary image is filled in and a recognition algorithm is designed to remove agglomerate particle ; on the basis of mathematical morphology two methods are adopted to segment agglomerate grains that are not agglomerated tightly ; the parameters of size and shape, perimeter, area, diameter, complexlity, longest feret diameter, shortest feret diameter etc, are extracted. this technique is applied in measurement of pearl powder ' s particle size
本文根據粒度圖像的特點,採用非線性對比度增強處理改善顆粒顯微圖像的對比度;對多種閾值分割方法進行比較,分析了它們的性能和用於粒度圖像的適用性,在此基礎上提出了一種基於梯度圖像的動態閾值分割方法;對獲取的顆粒二值圖像進行形態濾波和空洞填充,設計了識別演算法去除凝聚體;對重疊不太嚴重的粘結顆粒採用了兩種基於數學形態學的分割演算法;提取了周長、面積、粒徑、復雜度、最長feret徑、最短feret徑等大小和形狀特徵參數,對珍珠粉等粉體粒度進行了測量。In this paper, micro - cavity semiconductor laser ( mcsl ) with pillar vertical - cavity surface - emitting structure ( vcsel ) which has potential applications in optical communication and optical interconnect is theoretically analyzed, the calculation model that used to discuss the modal performance of rectangular columnar and cylinder vcsel with oxidized aperture is established by using vector field model. the numerical simulations in the case of cylinder structure show oscillating wavelength and threshold gain against inside and outside radius of laser, the layer refractive index and pair number of bragg mirror, thickness, position and oxidized material ' s refractive index of oxidized aperture, in detail. more practically, considering dos shell of laser as non - perfect one, or supposing that dos shell is separated from the laser, we can obtain more significative results
本工作以矢量場模型出發,對具有誘人應用前景的柱形垂直腔面發射結構( vcsel )的微腔半導體激光器( mcsl )進行了理論分析,建立了用於分析方柱形和圓柱形結構具有氧化孔徑層的激光器的模式特性的理論模型;對圓柱形結構情況進行了數值模擬,得到了振蕩波長、閾值增益隨激光器內外半徑、 bragg反射鏡層折射率、周期數以及氧化孔徑層厚度、位置和氧化物折射率的詳細變化規律;為使理論計算更接近實際,將外加金屬包殼視為非理想導體,或將金屬包殼與激光器結構隔開,分別對這兩種情況下的結果進行了討論。Secondly, other parameters such as temperature difference and emissivity of target and sky, molecular absorptive transmittance, instantaneous field of view ( ifov ), contrast threshold and radiant wavelength are discussed in detail
然後,對目標天空背景溫差、發射率,氣溶膠衰減系數,瞬時視場、對比度探測閾值以及輻射波長等參數作了詳細討論。The characteristic parameters of effective debris in a ferrograph have been calculated in the present thesis, like area, perimeter, aspect ratio and granularity, in which some methods have been adopted such as smoothing, filtering and thresholding and so on, according to tribological theories and computer technologies and digital image preprocessing
本論文基於摩擦學原理和計算機技術,通過對鐵譜片進行數字化圖像預處理,採用對譜片圖像的平滑、濾波以及閾值二值分割等方法,計算出譜片中特徵磨粒的一些特徵參量,如面積、周長、粒度以及縱橫比等。By use of g. d. shen ' s tunneling cascade theory we have fabricated high performance and high power tunneling cascade ingaas / gaas / algaas 950nm / 990nm double wavelength strained quantum well lasers on the basis of former tunneling cascade high power lasers and high brightness light emitting diodes. the lasers " two peak wavelength are 95 ? nm and 990 ? nm. el spectrum ' s fwhm is 3nm
在以往隧道級聯大功率應變量子阱激光器及高亮度發光管的理論研究與實驗的基礎之上,採用沈光地教授提出的隧道級聯思想,成功研製出基於ingaas gaas algaas材料的高性能大功率隧道級聯950nm及990nm雙波長應變量子阱激光器,激射波長分別為952 2nm和990 2nm , el譜的譜線寬度約3nm ,未鍍膜器件單面最大輸出光功率可達2w以上,閾值電流最低達120ma 。In this paper, some investigation and design as following. have been carried out on er - yb codoped phosphate glass waveguide laser first, three primary performance parameters of er - yb waveguide laser pump threshold power ; output power and slope efficiency have been commulated and analysed theoretically based on er ~ ( 3 + ) - yb ~ ( 3 + ) energy configuration ; rate equation of stable state and transmitting equation. the influences of er - yb ions concentration ; enabled waveguide length ; light dot radius of signal light and pump light ; reflectivity of output lens on three above parameters have been researched
首先,從er ~ ( 3 + ) - yb ~ ( 3 + )能級結構出發,結合激光穩態速率方程與傳輸方程,對鉺鐿波導激光器的三個主要性能參數:閾值功率、輸出功率、斜率效率作了理論計算分析,並研究了鉺、鐿離子濃度、光波導激活長度、信號光與泵浦光光斑半徑比例、輸出耦合鏡反射率對這三個關鍵性能參數的影響。One is to use fourier transformation to convert the source signal from time domain to frequency domain and to discard high frequency harmonious components upwards of 19 ( gb / t14953 - 93 d5. 3 demanding ), then to have static huffman coding to the quantized char array which is composed of reserved direct current component and basic wave and each high frequency " s amplitudes and angles. the other is to use discrete wavelet transformation to convert the source signal from time domain to frequency domain and to set the high frequency coefficients that its absolute value is smaller than the given threshold to zero, then to have dynamic huffman coding to the quantized char array which is composed of multiple, wavelet ' s level, datum length, low frequency coefficients and reserved high frequency coefficients. mass simulinks and analyses under the two circumstances have done to show that data compression ratio is small and the relative error is also small and within the permission of engineering and the compression problem can be solved in theory of measured datum of power system
第一種情況的壓縮方法為:採用傳統的傅立葉變換把原始信號從時間域變換到頻率域,舍棄20次及其以上的高次諧波成分(保證了gb / t14953 ? 93d5 . 3要求) ,然後對保留的直流分量、基波和各次諧波的幅值和相角數據量化后和量化時分別乘以的倍數系數構成一個數組,以字元形式保存,採用靜態huffman編碼對變換數據進行壓縮;採用離散小波變換把原始信號從時間域變換到頻率域,然後對分解得到的高頻系數進行閾值量化處理,對乘以的倍數系數、小波變換的階數、小波變換后的低頻、各級高頻以及原始數據長度、量化后的低頻系數以及保留的高頻系數大小、位置構成一個數組,以字元形式保存,採用動態huffman編碼對這個文件進行壓縮。The study of srs in non - linear optic fiber by simulink emphatically. the initial intensities of pump beam and stokes beam are similar, and small signal gain theory needs to amend have been pointed. srs comply with the special growth law, does not have " threshold " characteristics. lt depends not only on the intensity of pump beam but also on the intensity of stokes beam itself. even if the intensity of pump beam is weak, fhe srs effect is maybe still take place. in addition, the problem about srs effect depends on the number of channels, power in each channel and space of the channels, in a dwdm system has been studied
並著重論述了如何利用simulink研究非線性光纖光學中的受激喇曼效應,指出在光纖通信的情況兩個光束的初始強度相差不多時,小增益理論需要修正。 srs遵從特殊的增長規律,並不具有「閾值」特性。 stokes束的增長不僅依賴于泵浦波的強度,而且也和自身的強度有關系。On the basis of this, the effective reflective index with the variation of the carrier density is discussed. this paper also analyzed the random facet phase and the length of the cavity ' s influence on threshold characteristic. especially, the wavelength tuning characteristics have been investigated in detail when one segment works as absorbed region
在此基礎上,研究了每一段等效反射率譜曲線隨載流子濃度變化的情況;分析了邊界相位的不確定性以及激光器腔長對閾值特性的影響;重點討論了其中一段工作在吸收狀態下的波長調諧性質。In detail, the major work that have been done are as follows : l. irradiated by the 1. 06 m 1. 319 m 3. 8 m laser respectively, when the incident laser power density is between the saturation threshold and the damage threshold, the vibrating phenomenon and the zero - output phenomenon can be seen in the pv - type detectors " response curve
論文的主要工作有: 1分別用波長為1 . 06 m 、 1 . 319 m 、 3 . 8 m的激光輻照光伏型( pv ) hgcdte探測器,實驗發現,當輻照激光的功率密度大於其飽和閾值而小於其破壞閾值時,探測器的輸出存在「振蕩現象」和「零壓輸出現象」 。分享友人