<?xml version="1.0" encoding="UTF-8"?>
<!-- generator="FeedCreator 1.8" -->
<?xml-stylesheet href="https://wiki.yanding.com/lib/exe/css.php?s=feed" type="text/css"?>
<rdf:RDF
    xmlns="http://purl.org/rss/1.0/"
    xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
    xmlns:slash="http://purl.org/rss/1.0/modules/slash/"
    xmlns:dc="http://purl.org/dc/elements/1.1/">
    <channel rdf:about="https://wiki.yanding.com/feed.php">
        <title>研鼎知识库 yanding:成像基础知识:光学:辐射度学与光度学</title>
        <description></description>
        <link>https://wiki.yanding.com/</link>
        <image rdf:resource="https://wiki.yanding.com/lib/tpl/myconfluence/images/favicon.ico" />
       <dc:date>2026-05-09T04:53:41+00:00</dc:date>
        <items>
            <rdf:Seq>
                <rdf:li rdf:resource="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:cie%E6%A0%87%E5%87%86%E5%85%89%E8%A7%86%E6%95%88%E7%8E%87%E5%87%BD%E6%95%B0&amp;rev=1776149698&amp;do=diff"/>
                <rdf:li rdf:resource="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:lv_%E4%B8%8E_%E4%BA%AE%E5%BA%A6_%E5%87%BA%E5%B0%84%E5%BA%A6%E7%9A%84%E6%8D%A2%E7%AE%97&amp;rev=1774341486&amp;do=diff"/>
                <rdf:li rdf:resource="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E4%BA%AE%E5%BA%A6_luminance&amp;rev=1774341486&amp;do=diff"/>
                <rdf:li rdf:resource="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E5%85%89_light&amp;rev=1774341486&amp;do=diff"/>
                <rdf:li rdf:resource="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E5%85%89%E5%87%BA%E5%B0%84%E5%BA%A6&amp;rev=1777282173&amp;do=diff"/>
                <rdf:li rdf:resource="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E5%85%89%E9%80%9A%E9%87%8F_luminous_flux&amp;rev=1774341487&amp;do=diff"/>
                <rdf:li rdf:resource="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E5%8F%91%E5%85%89%E5%BC%BA%E5%BA%A6_luminous_intensity&amp;rev=1774341486&amp;do=diff"/>
                <rdf:li rdf:resource="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E5%8F%91%E5%85%89%E6%95%88%E8%83%BD&amp;rev=1774341487&amp;do=diff"/>
                <rdf:li rdf:resource="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E6%9C%97%E4%BC%AF%E4%BD%93&amp;rev=1776234514&amp;do=diff"/>
                <rdf:li rdf:resource="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E7%85%A7%E5%BA%A6_illuminance&amp;rev=1774341486&amp;do=diff"/>
                <rdf:li rdf:resource="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E7%AB%8B%E4%BD%93%E8%A7%92&amp;rev=1774596290&amp;do=diff"/>
                <rdf:li rdf:resource="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E8%BE%90%E5%B0%84%E4%BA%AE%E5%BA%A6&amp;rev=1777345220&amp;do=diff"/>
                <rdf:li rdf:resource="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%87%BA%E5%B0%84%E5%BA%A6&amp;rev=1777355566&amp;do=diff"/>
                <rdf:li rdf:resource="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BC%BA%E5%BA%A6&amp;rev=1774602851&amp;do=diff"/>
                <rdf:li rdf:resource="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E8%BE%90%E5%B0%84%E7%85%A7%E5%BA%A6&amp;rev=1777281839&amp;do=diff"/>
                <rdf:li rdf:resource="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E8%BE%90%E5%B0%84%E8%83%BD&amp;rev=1774589379&amp;do=diff"/>
                <rdf:li rdf:resource="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E8%BE%90%E5%B0%84%E8%83%BD%E5%AF%86%E5%BA%A6&amp;rev=1774589269&amp;do=diff"/>
                <rdf:li rdf:resource="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E8%BE%90%E5%B0%84%E9%80%9A%E9%87%8F&amp;rev=1778210886&amp;do=diff"/>
            </rdf:Seq>
        </items>
    </channel>
    <image rdf:about="https://wiki.yanding.com/lib/tpl/myconfluence/images/favicon.ico">
        <title>研鼎知识库</title>
        <link>https://wiki.yanding.com/</link>
        <url>https://wiki.yanding.com/lib/tpl/myconfluence/images/favicon.ico</url>
    </image>
    <item rdf:about="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:cie%E6%A0%87%E5%87%86%E5%85%89%E8%A7%86%E6%95%88%E7%8E%87%E5%87%BD%E6%95%B0&amp;rev=1776149698&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2026-04-14T06:54:58+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>yanding:成像基础知识:光学:辐射度学与光度学:cie标准光视效率函数</title>
        <link>https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:cie%E6%A0%87%E5%87%86%E5%85%89%E8%A7%86%E6%95%88%E7%8E%87%E5%87%BD%E6%95%B0&amp;rev=1776149698&amp;do=diff</link>
        <description>CIE标准光视效率函数

一、定义

CIE 标准光视效率函数 $V(\lambda)$ 是国际照明委员会（CIE）建立的基准响应函数，用于描述标准观察者在特定光度条件下对不同波长可见光的相对视觉敏感度。

其严格定义为：在给定光度条件下，若两种不同波长的可见光产生相同强度视觉感受时，则峰值敏感波长 $\lambda_m$$\Phi_{e,\lambda_m}$$\lambda$$\Phi_{e,\lambda}$$V(\lambda)$$L &gt; 5 cd·m⁻²$$V(\lambda)$$CIE 1988 (CIE 086-1990)$$4^\circ$\(V(\lambda)\)$4^\circ$\(V_{10}(\lambda)\)\(10^\circ\)\(y_{10}(\lambda)\)$L &lt; 0.005\ \mathrm{cd\cdot m^{-2}}$$V'(\lambda)$$0.005\ \mathrm{cd\cdot m^{-2}} &lt; L &lt; 5\ \mathrm{cd\cdot m^{-2}}$$$\varPhi_{\text{v}} = K_{\text{…</description>
    </item>
    <item rdf:about="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:lv_%E4%B8%8E_%E4%BA%AE%E5%BA%A6_%E5%87%BA%E5%B0%84%E5%BA%A6%E7%9A%84%E6%8D%A2%E7%AE%97&amp;rev=1774341486&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2026-03-24T08:38:06+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>yanding:成像基础知识:光学:辐射度学与光度学:lv_与_亮度_出射度的换算</title>
        <link>https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:lv_%E4%B8%8E_%E4%BA%AE%E5%BA%A6_%E5%87%BA%E5%B0%84%E5%BA%A6%E7%9A%84%E6%8D%A2%E7%AE%97&amp;rev=1774341486&amp;do=diff</link>
        <description>Lv 与 亮度、出射度的换算

背景：用对数标度表示胶片感光度

1960 年 ASA（美国标准协会，1969 年更名为美国国家标准学会——ANSI）发布了一项标准：


ASA PH2.5-1960. American Standard Method for Determining Speed of photographic Negative Materials (Monochrome, Continuous Tone). New York: United States of America Standards Institute.$$S_v = \log_2 (N S_x) \tag{1}$$$S_x$$S_v$$S_x$$S_v$$$E_v = A_v + T_v = B_v + S_v \tag{2}$$$A_v$$T_v$$B_v$$S_v$$$2^{E_v} = \frac{A^2}{T} = \frac{B S_x}{K} \tag{3}$$$$B = \frac{2^{E_v} \cdot K}{S_x} \quad (\textrm{fL}) \tag{4}$$$$1…</description>
    </item>
    <item rdf:about="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E4%BA%AE%E5%BA%A6_luminance&amp;rev=1774341486&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2026-03-24T08:38:06+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>yanding:成像基础知识:光学:辐射度学与光度学:亮度_luminance</title>
        <link>https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E4%BA%AE%E5%BA%A6_luminance&amp;rev=1774341486&amp;do=diff</link>
        <description>亮度（Luminance）

亮度是描述发光体（或反光 / 透射面）在指定方向上明暗程度的物理量，定义为该方向上的发光强度与发光面在垂直于该方向的投影面积之比。它直接决定人眼对物体 “明亮程度” 的感知，与发光体的发光效率、表面反射 / 透射特性密切相关。
$1\ \text{cd/m}^2 = 1\ \text{lm/(sr·m}^2\text{)}$$L = \frac{I_\theta}{S \cdot \cos\theta}$$L$${I_\theta}$$S$$ \theta$${S \cdot \cos\theta}$</description>
    </item>
    <item rdf:about="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E5%85%89_light&amp;rev=1774341486&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2026-03-24T08:38:06+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>yanding:成像基础知识:光学:辐射度学与光度学:光_light</title>
        <link>https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E5%85%89_light&amp;rev=1774341486&amp;do=diff</link>
        <description>光（Light）

光（Light）作为跨越光学工程与电子信息领域的核心载体，是能量传递与信息传输的关键媒介。从基础照明、高精度成像，到光纤通信、激光精密制造及前沿量子技术，光的应用已深植于现代科技命脉。从物理本质而言，$$E=h\nu=\frac{hc}{\lambda}$$$3\times10^8 m/s$$$c=\lambda*\nu$$$\lambda$$\nu$$\nu$$\lambda$$n_1 \sin \theta_1 = n_2 \sin \theta_2$</description>
    </item>
    <item rdf:about="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E5%85%89%E5%87%BA%E5%B0%84%E5%BA%A6&amp;rev=1777282173&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2026-04-27T09:29:33+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>yanding:成像基础知识:光学:辐射度学与光度学:光出射度</title>
        <link>https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E5%85%89%E5%87%BA%E5%B0%84%E5%BA%A6&amp;rev=1777282173&amp;do=diff</link>
        <description>光出射度（luminous exitance）

光出射度（符号：$M_v$，$M$）是光度学（Photometry）中表征面光源发光特性的核心物理量，用于量化表面向外发射可见光的能力，描述单位面积的总光输出，不考虑发射光线的方向分布。$2\pi$$d\Phi_v$$dA$$dA$$d\Phi_v$$$M_v = \frac{d\Phi_v}{dA}$$$d\Phi_v$$dA$$dA$$m^2$$\text{lm/m}^2$$E$$\mathrm{lx}$$1\ \mathrm{lm/m^2} = 1\ \mathrm{lx}$$M_v$$E$$$M_v = K_m \int_{0}^{\infty} M_{e,\lambda}(\lambda) V(\lambda) d\lambda$$$K_m = 683\ \text{lm/W}$$M_{e,\lambda}(\lambda)$$\lambda$$V(\lambda)$$[0, \infty)$$380\ \text{nm} \sim 780\ \text{nm}$$L_v$$$ M_v = \pi L_v $$$M_e$$\m…</description>
    </item>
    <item rdf:about="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E5%85%89%E9%80%9A%E9%87%8F_luminous_flux&amp;rev=1774341487&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2026-03-24T08:38:07+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>yanding:成像基础知识:光学:辐射度学与光度学:光通量_luminous_flux</title>
        <link>https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E5%85%89%E9%80%9A%E9%87%8F_luminous_flux&amp;rev=1774341487&amp;do=diff</link>
        <description>光通量（Luminous Flux）

定义

光通量是光度学中用于度量人眼可感知光功率的物理量，代表单位时间内光源发出的总光能量，可直观反映光源 “整体有多亮”。

（图像来源：&lt;https://en.wikipedia.org/wiki/Radiant_flux#/media/File:Photometry_radiometry_units.svg&gt;）

其计算原理是通过 ”$$\Phi_{v}(\lambda)=K_{m}V(\lambda)\Phi_{e}(\lambda)$$$\Phi_{v}(\lambda)$$K_{m}$$V(\lambda)$$\lambda=555nm $$V(\lambda)$$\Phi_{e}(\lambda)$$$1  lm = 1 cd  \times 1 sr$$$\Phi$$$\Phi = \int_{(\Omega)} I \mathrm{d}\Omega$$$\Omega = 4\pi\ \text{sr}$$\Phi$$$\Phi = \int_{(\mathrm{A})} E \mathrm{d}A$$…</description>
    </item>
    <item rdf:about="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E5%8F%91%E5%85%89%E5%BC%BA%E5%BA%A6_luminous_intensity&amp;rev=1774341486&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2026-03-24T08:38:06+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>yanding:成像基础知识:光学:辐射度学与光度学:发光强度_luminous_intensity</title>
        <link>https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E5%8F%91%E5%85%89%E5%BC%BA%E5%BA%A6_luminous_intensity&amp;rev=1774341486&amp;do=diff</link>
        <description>发光强度（Luminous Intensity）

定义

发光强度（Luminous Intensity）描述了光源在某方向上的强度，定义为发射到单位立体角内的光通量值。它是光源的固有属性，与光源面积、观测距离无关。


（图像来源：$$ I_v = \frac{\mathrm{d}\Phi_v}{\mathrm{d}\Omega} $$$I_v $$\Phi_v$$\Omega$$$\mathrm{cd} = \mathrm{lm} \cdot \mathrm{sr}^{-1}$$\( \theta, \varphi \)\( \Omega \)\( \Phi_v \)\[ \Phi_v = \iint_\Omega I_v(\theta, \varphi) \sin\theta \, \mathrm{d}\varphi \, \mathrm{d}\theta \]\[ I_v = K_m \int_0^\infty I_{e,\lambda}(\lambda) V(\lambda) \mathrm{d}\lambda \]\( K_m \)\( I_{e,\lambda}(\la…</description>
    </item>
    <item rdf:about="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E5%8F%91%E5%85%89%E6%95%88%E8%83%BD&amp;rev=1774341487&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2026-03-24T08:38:07+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>yanding:成像基础知识:光学:辐射度学与光度学:发光效能</title>
        <link>https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E5%8F%91%E5%85%89%E6%95%88%E8%83%BD&amp;rev=1774341487&amp;do=diff</link>
        <description>发光效能（Luminous efficacy）

一、定义

发光效能是衡量光源将能量转化为可见光效率的指标，定义为光通量（$\Phi_V$）与输入功率的比值，国际单位为流明每瓦（${lm·W}^{-1}$）。它是连接辐射度学与光度学的关键桥梁，它通过视见函数 $K(\lambda)$$$K = \frac{\Phi_V}{\Phi_e} = \frac{\int_0^\infty K(\lambda)\Phi_{e,\lambda}\mathrm{d}\lambda}{\int_0^\infty \Phi_{e,\lambda}\mathrm{d}\lambda}$$$\Phi_e$$\Phi_V$\(K_\text{m}\)$V(\lambda)=1$$K_m$$683\ \text{lm·W}^{-1}$$K'_m$$1700\ \text{lm·W}^{-1}$$K_{m,\text{mes}}$$K_{m,10}$$K_{m,M}$\(K_\text{m}\)$K_\text{m} \approx 683\ \text{lm·W}^{-1}$$$K_\text{m} = \f…</description>
    </item>
    <item rdf:about="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E6%9C%97%E4%BC%AF%E4%BD%93&amp;rev=1776234514&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2026-04-15T06:28:34+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>yanding:成像基础知识:光学:辐射度学与光度学:朗伯体</title>
        <link>https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E6%9C%97%E4%BC%AF%E4%BD%93&amp;rev=1776234514&amp;do=diff</link>
        <description>朗伯体

一、定义

朗伯体（又称余弦辐射体、理想漫射体）是光学、辐射度学与光度学中的理想化模型，指表面的辐射亮度（L）在所有观测方向上均保持恒定的物体，即辐射亮度 L 与观测方向无关。$$ I_\theta = I_n \cos\theta $$$I_\theta$$\theta$$\text{W}/(\text{sr})$$I_n$$\theta=0$$\theta$</description>
    </item>
    <item rdf:about="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E7%85%A7%E5%BA%A6_illuminance&amp;rev=1774341486&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2026-03-24T08:38:06+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>yanding:成像基础知识:光学:辐射度学与光度学:照度_illuminance</title>
        <link>https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E7%85%A7%E5%BA%A6_illuminance&amp;rev=1774341486&amp;do=diff</link>
        <description>照度 (Illuminance)

照度

照度是表征被照表面单位面积上接收光通量多少的物理量，直接反映表面被照亮的程度。其大小取决于光源的发光强度、照射距离及角度（遵循平方反比定律和余弦定律），与被照物体的材质、反射特性等自身属性无关。$1\ \text{lx} = 1\ \text{lm/m}^2$$E = \frac{\varPhi}{S}$$E $$\varPhi$$S$$d$$4\pi d^2$</description>
    </item>
    <item rdf:about="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E7%AB%8B%E4%BD%93%E8%A7%92&amp;rev=1774596290&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2026-03-27T07:24:50+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>yanding:成像基础知识:光学:辐射度学与光度学:立体角</title>
        <link>https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E7%AB%8B%E4%BD%93%E8%A7%92&amp;rev=1774596290&amp;do=diff</link>
        <description>立体角

定义：

若一个任意形状的物体对球心所张开的区域，在半径为 r 的球面上投影面积为 A，则该物体对球心所张的立体角（符号记为$\Omega$）为：$$\Omega = \frac{A}{r^2}$$
单位：球面度sr


（图像来源：&lt;https://commons.wikimedia.org/wiki/File:Angle_solide_coordonnees.svg&gt;）</description>
    </item>
    <item rdf:about="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E8%BE%90%E5%B0%84%E4%BA%AE%E5%BA%A6&amp;rev=1777345220&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2026-04-28T03:00:20+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>yanding:成像基础知识:光学:辐射度学与光度学:辐射亮度</title>
        <link>https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E8%BE%90%E5%B0%84%E4%BA%AE%E5%BA%A6&amp;rev=1777345220&amp;do=diff</link>
        <description>辐亮度

辐亮度（Radiance）定义为辐射源在某一方向上，单位投影面积、单位立体角内发出的辐射通量，记为 \(L\)。

单位：\(\mathrm{W \cdot sr^{-1} \cdot m^{-2}}\)（瓦特每球面度每平方米）。


数学表达式：

$$L = \frac{dI}{dA \cos\theta} = \frac{d^2 \Phi}{dA \cos\theta \, d\Omega}$$
式中：$L$为辐亮度；$I$为辐射强度；$\Phi$为辐射通量；$A$$\theta$$\Omega$$L$$\rho$$$ M = \rho E $$$$ M = \pi L $$$$ L = \frac{\rho E}{\pi} $$$L$$E$$\rho$…</description>
    </item>
    <item rdf:about="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%87%BA%E5%B0%84%E5%BA%A6&amp;rev=1777355566&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2026-04-28T05:52:46+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>yanding:成像基础知识:光学:辐射度学与光度学:辐射出射度</title>
        <link>https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%87%BA%E5%B0%84%E5%BA%A6&amp;rev=1777355566&amp;do=diff</link>
        <description>辐射出射度

辐射出射度（radiant exitance），记为$M$，是指单位时间内由表面单位面积向其外侧半球空间发出的辐射通量，单位为$W/m^2$。

其数学表达式为：
$$M = \frac{d\Phi}{dA}$$

与辐亮度的关系

辐射出射度可表示为表面在所有出射方向上辐亮度的积分：$$M = \int_{\Omega} L(\omega) \cos\theta \, d\omega$$$L(\omega)$$\omega$$\theta$$\Omega$$$M = \rho E$$$\rho$$E$$\mathrm{W/m^2}$$$M = \pi L$$$lm/m^2$</description>
    </item>
    <item rdf:about="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BC%BA%E5%BA%A6&amp;rev=1774602851&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2026-03-27T09:14:11+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>yanding:成像基础知识:光学:辐射度学与光度学:辐射强度</title>
        <link>https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BC%BA%E5%BA%A6&amp;rev=1774602851&amp;do=diff</link>
        <description>辐射强度

定义：辐射源在某个特定方向上、单位立体角内发射的辐射通量，符号记为$I$。


数学表达式：$$I = \frac{d\Phi}{d\Omega}$$
辐射强度是点源的核心属性

1.对于恒星，观测距离 r 以光年计，对探测器来说，恒星的张角极小（以毫角秒计），可视为点源，以恒星中心为球心的球面，探测器（平面）面积与球面面积差异可忽略，故立体角 $\Omega$$A$$r$$\Omega = \frac{A}{r^2}$$\Phi $$\Omega$$ I = \frac{d\Phi}{d\Omega}$$D$$ I = \frac{d\Phi}{d\Omega}$…</description>
    </item>
    <item rdf:about="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E8%BE%90%E5%B0%84%E7%85%A7%E5%BA%A6&amp;rev=1777281839&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2026-04-27T09:23:59+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>yanding:成像基础知识:光学:辐射度学与光度学:辐射照度</title>
        <link>https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E8%BE%90%E5%B0%84%E7%85%A7%E5%BA%A6&amp;rev=1777281839&amp;do=diff</link>
        <description>辐射照度

定义：单位时间内，照射到单位面积表面上的辐射通量（功率），符号记为$E$。

单位：$W / m^{2}$

数学表达式：$$E = \frac{d\Phi}{dA}$$

点源对微面元的照度与强度的关系

对于各向同性点光源，其在某一方向上的辐射强度为 $I$$W/sr$$r$$dA$$dA$$d\Omega = \frac{dA}{r^2}$$d\Phi = I \cdot d\Omega = I \cdot \frac{dA}{r^2}$$E = \dfrac{d\Phi}{dA}$$$E = \frac{d\Phi}{dA} = \frac{I \cdot \dfrac{dA}{r^2}}{dA} = \frac{I}{r^2}$$</description>
    </item>
    <item rdf:about="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E8%BE%90%E5%B0%84%E8%83%BD&amp;rev=1774589379&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2026-03-27T05:29:39+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>yanding:成像基础知识:光学:辐射度学与光度学:辐射能</title>
        <link>https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E8%BE%90%E5%B0%84%E8%83%BD&amp;rev=1774589379&amp;do=diff</link>
        <description>辐射能

 一、定义

辐射能（Radiant Energy）是电磁辐射或引力辐射在发射、传输或吸收过程中所携带的能量，是辐射度学中最基础的能量量度，用于描述电磁波在特定时间段内做功的本领，符号记为：$Q_e$$$Q_e = \int_{t_1}^{t_2} \Phi_e(t) dt$$$\Phi_e(t)$$t_1-t_2$</description>
    </item>
    <item rdf:about="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E8%BE%90%E5%B0%84%E8%83%BD%E5%AF%86%E5%BA%A6&amp;rev=1774589269&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2026-03-27T05:27:49+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>yanding:成像基础知识:光学:辐射度学与光度学:辐射能密度</title>
        <link>https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E8%BE%90%E5%B0%84%E8%83%BD%E5%AF%86%E5%BA%A6&amp;rev=1774589269&amp;do=diff</link>
        <description>辐射能密度

一、定义

辐射能密度（Radiant energy density）定义为单位体积空间内所储存的电磁辐射能量，通常记为\(w\) 或 \(u\)，描述了辐射场在空间中的能量分布密集程度。

国际单位制（SI）单位为：焦耳每立方米 (\(J/m^3\)\([M L^{-1} T^{-2}]\)$$w = \frac{dQ}{dV}$$\(dQ\)\(dV\)$Q = 8000 J$$V= 23 L= 0.023 {m}^3$$w \approx 347\,826.09 {J/m}^3$\(E\)\(B\)$$w = \frac{1}{2}\left(\varepsilon E^2 + \frac{1}{\mu} B^2\right)$$\(E\)\(c\)\(w = \dfrac{4E}{c}\)\(w = \dfrac{E}{c}\)\(P\)$P = \frac{1}{3} w$$$w = a T^4$$\(a = \frac{4\sigma}{c}\)\(\sigma\)\(w_\lambda\)$$w = \int_0^\infty w_\lambda d\lam…</description>
    </item>
    <item rdf:about="https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E8%BE%90%E5%B0%84%E9%80%9A%E9%87%8F&amp;rev=1778210886&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2026-05-08T03:28:06+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>yanding:成像基础知识:光学:辐射度学与光度学:辐射通量</title>
        <link>https://wiki.yanding.com/doku.php?id=yanding:%E6%88%90%E5%83%8F%E5%9F%BA%E7%A1%80%E7%9F%A5%E8%AF%86:%E5%85%89%E5%AD%A6:%E8%BE%90%E5%B0%84%E5%BA%A6%E5%AD%A6%E4%B8%8E%E5%85%89%E5%BA%A6%E5%AD%A6:%E8%BE%90%E5%B0%84%E9%80%9A%E9%87%8F&amp;rev=1778210886&amp;do=diff</link>
        <description>辐射通量

辐射通量（Radiant Flux）是辐射能量随时间的变化率，表征单位时间内发射、传输或接收的总辐射能（功率），符号记为$\Phi$或$P$，数学表达式为：

$$\Phi_\text{e} = \frac{\mathrm{d}Q_\text{e}}{\mathrm{d}t}$$
其中， $Q_\text{e}$为辐射能量，$t$ 为时间。

单位：$\Phi$$O$$l_0$$R$$\mathrm{d}A$$$\mathrm{d}P = E\mathrm{d}A = \frac{I\cos\alpha}{l^2}\mathrm{d}A \tag{1}$$$\mathrm{d}A = \rho\mathrm{d}\theta\mathrm{d}\rho$$\cos\alpha = l_0/l = l_0/\sqrt{\rho^2 + l_0^2}$$\rho$$\theta$$R$$$P = \int\mathrm{d}P = Il_0\int_0^{2\pi}\mathrm{d}\theta\int_0^R\frac{\rho}{(\rho^2 + l_0^2)^{3/2…</description>
    </item>
</rdf:RDF>
