[工學(xué)]建筑環(huán)境學(xué)chapter41-2 thermal comfortable-文庫吧
2025-02-07 00:50 本頁面
【正文】 色性 is the ability of a light source to reveal the colour appearance of surfaces. ? reference source such as daylight日光 ? colour rendering index（ Ra) which has a value of 100 for an ideal lamp. ? Practical sources of white light range in Ra value between 50and 90 ?顯色性是指燈光對(duì)其照射的物體的影響作用。 The CIE colour rendering groups Group Ra Importance Typical application 1A 90...100 accurate colour matching Galleries畫廊，美術(shù)館 , medical examinations, colour mixing 1B 80...90 accurate colour judgement Home, hotels, offices, schools 2 60...80 moderate colour rendering Industry, offices, schools 3 40...60 accurate colour rendering is of little importance Industry, sports halls 4 20...40 accurate colour rendering is of no importance Traffic lighting Colour rendering index for different light sources Light source Colour rendering group Incandescent 白熾燈 1A Metal halide 金屬鹵燈 1A ... 2 Fluorescent 熒光燈 1A ... 3 High pressure sodium 高壓鈉燈 1B ... 4 Low pressure sodium 低壓鈉燈 4 7 Artificial Lighting 人工照明 Lamps 燈 how to evaluate the Properties of lamps 如何評(píng)價(jià)燈的性能？ 1) Luminous efficacy 光效 2) Life 壽命 3) Colour temperature Correlated Colour Temperature (CCT) 相關(guān)色溫 The lower values of colour temperature indicate light with a higher red content. 4) Colour rendering 顯色性 the fist type of artificial light Incandescent lamps 白熾燈 passing an electric current through a filament of metal and raising the temperature to white heat. When the metal is incandescent熾熱的 , at around 2800K , useful quantities of light are given off. 1) Most General Incandescent lamps is tungsten filament lamp. 最常見的白熾燈是鎢絲燈 mon light bulb 普通燈泡 be clear or frosted透明的或磨砂的 . contains either a vacuum or an inert gas to prevent oxidation of the hot filament. The cost is low 費(fèi)用低 its installation is simple 安裝簡單 relatively short life 壽命短 1000h the labour costs of replacement to be high更換所需人工費(fèi)高 The low luminous efficacy 光效低 lm/w high electrical running costs 費(fèi)電 ? Only about 5% of the electrical energy visible light ? most of the energy consumed is given off as heat, especially radiant heat. Characters of a tungsten filament lamp 鎢絲燈的特點(diǎn) 2) The improved incandescent lamps: Reflecting lamps 改進(jìn)后的白熾燈： 反射型燈 a) Spot lamps 聚光燈 : glass bulb silvered inside and shaped to form a parabola 拋物線 with the filament at the focus. b) Sealed beam lamps密封光束燈 use similar techniques C) Crownsilvered lamps 銀冠燈 are standard filament lamps where the glass bulb is silvered in front. gives narrow beams of light some other improved incandescent lamp 3) Tungstenhalogen lamps鹵鎢燈 ? Halogen 鹵素 ? A small quantity of a halogen gas, . iodine 碘 or bromine溴 ? run at higher temperatures This gives it a higher efficacy (10–30 lm/W). 1500h 4) Lowvoltage system ? uses 12volt ? lowvoltage bulbs need a lower resistance ? filament can be shorter, thicker and stronger. ? good directional qualities ? popular in shops for the displ
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