200817651 九、發明說明： 【發明所屬之技術領域】 本發明係有關-種距離量測系 位影像中像素值與距離的線性 =疋—種利用數 距離量測系統。 〗關係以進行距離量測之 【先前技術】 傳統上應用於環境實地 直接量測及間接量測。 j之方法，主要可分為 在直接量測的部分，如交通事 查，係直接利用皮尺在現場針 琢、g的現場勘 可以最直接且迅速的方式進‘、，目對4距離的量測，如此 方式直接依賴量測人員的量測；二=對：Γ該量剛 人員的偏頗所造成。 々入马的决差或者是量測 ^間接量測的部分，如等 置一標準尺或一標準大小之比 ^ 待測現場放 離與比較物之比例，可計算出二卜:待f二點間之距 此，受場所之限.===離，但 容易受Λ之的白^^1 中是直接量測或是間接量測皆 制。因而目前尚：因此亦會受到現場環境及時間的限 到壤境及人為操作之影響的距離量測系統。且不而叉 【發明内容】 本發明之目的在於提供一種距離量測系統，利用影像 200817651 ===:!;資訊的距離量測系蛛，以透過真 貝的〜像、、、己錄末避免人為的目測誤差。 為達上述目的，本發明係提供距離 括：一影像擷取裝置，用以拇& —人 w +用乂擷取包含一目標物的影像圖形 射光源，用以投射-與前述影像掏 3==上平行之雷射光束’並於前述目標物 =二;以:及-計算單元，用以讀取前述 雷射光源的投射亮點之掃描線， ΐ，線之位置至前犧'線中心 之曰1拍驢去=&十异所述像素值與前述影像畫面資訊 值像素值比值，進而利用前述像素值比 掃描線中心點的實際長度與前述影 ;畫=之實際最大拍攝長度的長度比值成正比之關 述影像晝面資訊之實際最大減長度，以及根 ί=ϊί=ί與幾何定理計算前述目標物與前述影 像擷取裝置之間的實際距離。 、為達上述目的，本發明復提供一距離量測方法，包含 =步驟：投射-雷射光束於—目標物之表面以形成一投 、巧點；擷？包含前述投射亮點之影像晝面資訊·，計算前 =影像畫面貧訊中包含前述投射亮點之掃描線的中心點至 =述投射亮點之像素值；計算前述掃描線之像素值與前述 帚=線中心點至前述投射亮點之像素值的像素值比值，·利 用則述像素值比值係與前述投射亮點至掃描線中心點的實 際長度與前述影像晝面資訊之實際最大拍攝長度的長度比 值成正比之關係，計算前述影像晝面資訊之實際最大拍攝 長度；以及根據前述最大拍攝長度與幾何定理計算前述目 “物之實際長度，或前述目標物與前述影像擷取裝置之間 200817651 的實際距離。 綜上所述，本發明之距離量測系統係可廣泛利用於各 種距離量測之應用，利用影像擷取裝置與雷射光源結合的 簡易結構達到同時進行影像紀錄及距離量測之功能。 本發明之前述目的或特徵，將依據後附圖式加以詳細 說明，惟需明瞭的是，後附圖式及所舉之例，祇是做為說 明而非在限制或縮限本發明。 【實施方式】 本發明係為一利用數位影像中像素值與距離的關係 以進行距離量測之距離量測系統。參考第一圖為本發明之 功能方塊圖，本發明係以一雷射光源20投射一雷射光束於 一目標物30之表面，再以一數位相機10擷取一影像晝面 資訊，並以一計算單元40計算該影像晝面資訊之像素值， 以利用像素值與距離的比例關係換算出目標物30的長度 或與該數位相機10的距離。 參考第二圖為本發明距離量測系統以像素值量測距 離的示意圖，該數位相機10係分別於CD直線及EF直線 的位置擷取影像畫面資訊，且該雷射光源20並分別於CD 直線及EF直線投射一亮點，其中： OP :數位相機10之光學原點； 尸d、尸厂：雷射光源20分另丨J於CD平面及EF平面之投 射亮點； Ο :數位相機10拍攝之掃描平面中心點； /¾ :該CD平面與數位相機10表面之距離； :該EF平面與數位相機10表面之距離； 200817651 t:0P與數位相機10表面之距離； 、％ :數位相機10 攝之實際最大拍攝長度； 平面及EF平面所能拍 认：心、心與0點之距離； 該數位攝影機10之最大拍攝角度； ·數位相機1〇單一 又 以及 早知彳田線之隶大拍攝像素值； 心’：〜與〜分別至㈣距離之像素值。 參考第三圖為該數位相 圖。其中，Ζ軸為該數位相像操取的透視投影 取方向’該數位相機10即、ί : 7'光學原點0p的影像擷 並取得一如包含A點及軸方向進行影像擷取， 資訊。且該Z軸方向亦為的掃描平面之影像晝面 轴穿越該掃描平面之―點厂^描平面之法線方向，而該Z 心點。c點至D點之直〇點，亦為該掃描平面之中 平面亡與〇點相交之掃直線即為-掃描 位於每一條掃描線之1/2、、 母知描平面上之ο點即 復參考第二圖，該雷射;;素點之位置。 與該數乜相機10之影"、斤投射之雷射光束係 源20之雷射光束得垂象直#取方向互相平行，使得該雷射光 面，且該雷射光束於 ；立目機1〇之任一掃描平 掃描平面之平面之投射亮點…、⑸皆與該 』你得相同的距離(认）。 性，使得^之投射亮點與G點等距離的特 統之二組雷 ikfD)〇 0 、任一抑^田十面取得一相同之水平坧 r 遠位相機10所拍攝之影像晝面資訊的掃描 200817651 時間與被掃描物的水平距離有著線性比例關係，因此該計 算單元40便可直接以像素值的大小代表被掃描物的水平 距離，如下列公式：200817651 IX. DESCRIPTION OF THE INVENTION: TECHNICAL FIELD OF THE INVENTION The present invention relates to a linear measurement of pixel values and distances in a distance measurement system image. 〗 Relationships for distance measurement [Prior Art] Traditionally applied to environmental field direct measurement and indirect measurement. The method of j can be mainly divided into the part of direct measurement, such as traffic investigation, which is the direct and quick way to use the tape measure in the field, and the g-site survey can be entered in the most direct and rapid way. Measurement, this way directly depends on the measurement of the measurement personnel; two = right: Γ the amount of the person just caused by the bias. If you break into the horse's decision or measure the part of the indirect measurement, such as the ratio of a standard ruler or a standard size ^ the ratio of the site to be measured and the comparison, you can calculate the second b: The distance between the points is limited by the location. === away, but the white ^^1 that is easily affected is directly measured or indirectly measured. Therefore, there is still a distance measurement system that is limited by the environment and time of the site and affected by the soil and human operations. The present invention aims to provide a distance measuring system, which uses the image 200817651 ===:!; the distance measurement of the information is used to measure the spider, to avoid the image of the true shell, Artificial visual error. In order to achieve the above object, the present invention provides a distance: an image capturing device for thumb & - human w + for capturing an image pattern light source including a target for projecting - and the aforementioned image 掏 3 ==Upper parallel laser beam 'and the target object=2; to: and - calculation unit for reading the scanning line of the projected bright spot of the aforementioned laser source, ΐ, the position of the line to the center of the front sacrificial line Then, the ratio of the pixel value to the pixel value of the video image information value is used, and the actual value of the pixel value is compared with the actual length of the scan line center point and the actual maximum shooting length of the image. The length ratio is proportional to the actual maximum decrement length of the image facet information, and the root ί=ϊί=ί and the geometric theorem calculate the actual distance between the object and the image capturing device. In order to achieve the above object, the present invention provides a distance measuring method comprising the steps of: projecting a laser beam onto the surface of the target to form a throwing point; The image information including the image of the projected bright spot, the pixel value of the scan line including the projected bright spot in the image data before the calculation is calculated to the pixel value of the projected bright spot; and the pixel value of the scan line and the 帚= line are calculated. The pixel value ratio of the pixel value of the center point to the projected bright spot, and the pixel value ratio is proportional to the ratio of the actual length of the projected bright point to the center point of the scan line to the length of the actual maximum shot length of the image mask information. The relationship between the actual maximum shooting length of the image and the actual length of the image; and the actual length of the object or the actual distance between the target and the image capturing device of 200817651 according to the maximum shooting length and geometric theorem. In summary, the distance measuring system of the present invention can be widely used in various distance measuring applications, and the simple structure combining the image capturing device and the laser light source can achieve the functions of simultaneous image recording and distance measurement. The foregoing objects or features of the invention will be described in detail in accordance with the following drawings, but need to be understood The present invention is intended to be illustrative, not limiting or limiting the invention. [Embodiment] The present invention is directed to the use of a relationship between pixel values and distances in a digital image for distance. Measuring distance measuring system. Referring to the first figure, a functional block diagram of the present invention, the present invention projects a laser beam 20 onto a surface of a target 30 by a laser source 20, and then takes a digital camera 10 to capture one. The image is scanned and the pixel value of the image information is calculated by a calculating unit 40 to convert the length of the object 30 or the distance from the digital camera 10 by the proportional relationship between the pixel value and the distance. For the distance measurement system of the present invention, the distance measurement is performed by using a pixel value, and the digital camera 10 captures image image information at a position of a CD line and an EF line, respectively, and the laser light source 20 is respectively on a CD line and an EF line. Projecting a bright spot, where: OP: optical origin of the digital camera 10; corpse d, corpse: laser light source 20 points 丨 J on the CD plane and the EF plane projection highlights; Ο: the scanning plane center of the digital camera 10 Point; /3⁄4 : the distance between the CD plane and the surface of the digital camera 10; : the distance between the EF plane and the surface of the digital camera 10; 200817651 t: the distance between the 0P and the surface of the digital camera 10; , %: the actual maximum of the digital camera 10 Shooting length; plane and EF plane can be photographed: distance between heart, heart and 0 point; the maximum shooting angle of the digital camera 10; · digital camera 1 〇 single and early knowledge of the large pixel value of the 彳田 line; Heart ': ~ and ~ respectively to (4) the pixel value of the distance. Refer to the third figure for the digital phase diagram, where the Ζ axis is the direction of the perspective projection of the digital image taken 'the digital camera 10 ie, ί : 7' The image of the optical origin 0p is obtained as image capturing information including the point A and the axis direction, and the image of the scanning plane of the Z-axis direction is the axis of the scanning plane. The normal direction, and the Z heart point. The straight point from point c to point D is also the line that intersects the plane and the point in the scanning plane. The scanning is located at 1/2 of each scanning line and ο at the mother's drawing plane. Referring to the second figure, the laser; the position of the prime point. The laser beam of the laser beam source 20 of the digital camera 10 is projected perpendicularly to the direction of the laser beam, and the laser beam is incident on the laser beam; 1) Any of the projected bright spots on the plane of the flat scan plane..., (5) are the same distance as the "you". Sexuality, so that the projected highlights of ^ are equidistant from the G-point, the two groups of Lei ikfD) 〇0, and any one of the tens of meters, the same level 坧r, the image of the image taken by the remote camera 10 The scan 200817651 has a linear proportional relationship with the horizontal distance of the scanned object, so the calculation unit 40 can directly represent the horizontal distance of the scanned object by the size of the pixel value, as shown in the following formula:
D =^η^χΙ)D =^η^χΙ)
NF 參考三角定理可得以下公式： HD =-^DC〇t^max ~hS =^2^f C〇^max ~ 將上述像素值與水平距離的比例關係帶入三角定理 可得以下公式： HD =I(^^^xDr)xcot0max -hsThe NF reference triangle theorem can be obtained by the following formula: HD =-^DC〇t^max ~hS =^2^f C〇^max ~ Bring the above-mentioned pixel value to the horizontal distance proportional relationship into the triangle theorem to obtain the following formula: HD =I(^^^xDr)xcot0max -hs
Hf =臺(^^xA)xc〇t0max 一\ 其中，、心二個參數值係可經由一計算模型事 先計算出該、心二個參數值的大小。因此根據該等 參數值的大小，該計算單元40在計數％、力值之後即可 求得&、的值。 參考第四圖為計算心二個參數值的計算模型 之系統架構圖。該計算模型包括該數位相機10、二組垂直 量尺41以及二組水平量尺42。其中，該等水平量尺42係 分別與該數位相機10的表面之垂直距離為，而該 等垂直距離係可輕易由該等垂直量尺41量測出。 而為了增加\量測的準確性，於計算參數值的模型中，係 200817651 將該數位相機10所能拍攝之最大角度2(9_χ進一步縮限為 ，如此可去除該數位相機10所拍攝之掃描平面的邊 緣，避免模糊邊緣的產生，以增加量測的準確性。 參考第四圖，當該數位相機10之最大拍攝角度限制 為2仏時，該數位相機10於該等水平量尺42之最大水平 拍攝距離亦可由該等水平量尺輕易量測出，分別為、 。根據三角定理可得下列公式： K +K\ =2Dm] c0t^s K+hm2=^Dm2C〇tes 將上述公式加以整理，即可得到coi久的關係式如下 所示： * 1 K\ ^Kl =2^Drn\ -Dml)C〇t^s C〇t0 =2-^—Hf = station (^^xA)xc〇t0max a \ where, the heart two parameter values can be calculated by a calculation model to calculate the size of the two parameters of the heart. Therefore, based on the magnitude of the parameter values, the calculation unit 40 can obtain the value of &, after counting the % and the force value. Refer to the fourth figure for the system architecture diagram of the calculation model for calculating the two parameter values of the heart. The calculation model includes the digital camera 10, two sets of vertical scales 41, and two sets of horizontal scales 42. The horizontal distances of the horizontal scales 42 are respectively perpendicular to the surface of the digital camera 10, and the vertical distances can be easily measured by the vertical scales 41. In order to increase the accuracy of the measurement, in the model for calculating the parameter value, the maximum angle 2 (9_χ) that can be taken by the digital camera 10 is further reduced to so that the scanning of the digital camera 10 can be removed. The edge of the plane avoids the generation of blurred edges to increase the accuracy of the measurement. Referring to the fourth figure, when the maximum shooting angle of the digital camera 10 is limited to 2, the digital camera 10 is at the horizontal scale 42 The maximum horizontal shooting distance can also be easily measured by the horizontal measuring scales, respectively. According to the triangle theorem, the following formula can be obtained: K + K\ = 2Dm] c0t^s K+hm2=^Dm2C〇tes Finishing, you can get the long relationship of coi as follows: * 1 K\ ^Kl =2^Drn\ -Dml)C〇t^s C〇t0 =2-^-
Dm2 - Dm\ 且參數值的大小亦可藉由以上關係式，將 重新以該數位相機1〇於最大拍攝角度為2 所對應之值代入上述關係式以計算得知。進一步將上述 見的關係式加以整理，可獲得以下關係式： K^Kl K + K\ Dm\ 因此即可獲得參數值心的大小： S Dm\ ~ Dml 參考第五圖為驗證該數位相機10之畸變差（Radial Distortion)的格線圖。利用第五圖驗證一由Panasonic所生 200817651 產之數位_ F X 7 ’紐位相機F χ 7係於每 500萬像素值。參考第六圖為該數位相機印 線，灰階值圖，其中色系越黑所代表之灰階值越小。另二 考第七圖為該數位相機FX7於相鄰的二垂直格線間之像^ 值的統計圖’該等相鄰的垂直格線間之像素值皆位於C 之’由圖中所示可知該數位相機FX7之顯示具有 本發明係利用該數位相機FX7與一 5毫瓦(的爺 射光源(AStroPenGLM_0505_p)以進行距離量測之驗證: 目機F X 7以量測白板之距離。將該雷射光源固定 致使，、辑射光束與該數位相機FX7之影像擷取平面平 其中該雷射光束與該數位相機F χ 7之掃描平面 距離A*為12公分(cm)。 的 f考第八A圖為當白板實際距離為120公分時之影像 f面貝讯:其中該雷射光源係於該白板之表面形成一投射 亮點。並參考第八Β圖為通過該投射亮點之-水平掃描線 的像^值’如圖所示可知’於投射亮點之位置的灰階值即 大為提升’亦即在該掃描線第1〇5〇個像素附 大於平均之灰階值。 自值退 參考第九Α圖為當白板實際距離為44〇公分時之影像 晝面資訊，其中由於該白板距離較遠，因此該雷射光=於 該白板上之，射亮點在所擷取之影像晝面資訊中所佔的面 積較小。並參考第九B圖為通過該投射亮點之一水平掃描 線的像素值，如圖所示可知，於投射亮點之位置的灰階值 即^為提升’糾找掃财帛㈣他附近的灰階 值遠大於平均之灰階值。 由於一般數位相機所擷取出之數位影像資訊為JpG檔 11 200817651 二二' s彺，相當大的高頻失真，因此本發明進 '、為一單位取移動平均值，以判斷較準確之 火P白值數據。由第人B1J及第九B圖可知，根據取移動平 均值之後的灰階錄據，可朗灰階值的大小輯算出投 射亮點的位置。本發明進—步利用—臨界值(Thresh〇ld)以 作為判斷投射亮點的位置，參考下列關係式：Dm2 - Dm\ and the size of the parameter value can also be calculated by substituting the value corresponding to the maximum shooting angle of the digital camera 1 into the above relationship by the above relationship. Further sorting the relationship described above, the following relationship can be obtained: K^Kl K + K\ Dm\ Therefore, the size of the parameter value heart can be obtained: S Dm\ ~ Dml Refer to the fifth figure to verify the digital camera 10 The grid diagram of the Radial Distortion. Use the fifth picture to verify that the number produced by Panasonic 200817651 is _ F X 7 ' New Zealand camera F χ 7 is at 5 million pixel value. Referring to the sixth figure, the digital camera print, the gray scale value map, wherein the darker the color system, the smaller the gray scale value. The second picture is the statistical diagram of the image of the digital camera FX7 between the adjacent two vertical grid lines. The pixel values between the adjacent vertical grid lines are all located at C'. It can be seen that the display of the digital camera FX7 has the invention utilizing the digital camera FX7 and a 5 milliwatt (JustPenGLM_0505_p) for distance measurement verification: the camera FX 7 measures the distance of the whiteboard. The laser light source is fixed, and the image beam is level with the image capturing plane of the digital camera FX7, wherein the scanning plane distance A* between the laser beam and the digital camera F χ 7 is 12 cm (cm). Figure 8A shows the image f-plane when the actual distance of the whiteboard is 120 cm: the laser source forms a projected bright spot on the surface of the whiteboard, and refers to the eighth map as the horizontal highlight through the projected bright spot. As shown in the figure, the value of the line 'value' is as large as the value of the gray level at the position of the projected bright point, that is, the first pixel of the scan line is larger than the average gray level value. Refer to the ninth map for the shadow when the actual distance of the whiteboard is 44〇 cm. According to the face information, because the whiteboard is far away, the laser light is on the whiteboard, and the light-emitting point occupies a small area in the captured image information. The pixel value of the horizontal scanning line of one of the projected bright spots, as shown in the figure, the grayscale value at the position of the projected bright spot is the boosting of the 'finishing sweeping money' (four) the grayscale value near him is much larger than the average grayscale value. Since the digital image information extracted by a general digital camera is JpG file 11 200817651 22's, a relatively large high-frequency distortion, the present invention enters a unit to take a moving average to determine a more accurate fire. P white value data. It can be known from the first person B1J and the ninth B picture that the position of the projected bright point is calculated according to the gray scale record after taking the moving average value. The present invention further utilizes the criticality. The value (Thresh〇ld) is used as a position to judge the projected bright point, and the following relationship is referred to:
Threshold = mean{S) + (max(S) - mean(S)) · K 其中，S係為該條掃描線之像素值，而夂為比重參數， 用以校準臨界值的計算。於本發明之驗證步驟中，係將比 重參數尤設為0.8。根據該臨界值即可準確計算出投射亮 點的位置。 # ^ 付知該投射免點與掃描線中心點（zwax/2)的像素值(Ab) 之後’並藉由計算模型40計算出該數位相機ρχ7的參數 值(/^=4.0273公分，C6^wa;c=2.8726)，即可計算出白板與該 數位相機FX7之距離0¾)。參考下表即為利用本發明之系 統所計算之距離及其誤差： 真實的^ nd 量測的& 誤差（％) 60 532.5 58.2466 -2.9223 80 407 77.4490 -3.1888 100 331.5 96.0055 -3.9945 120 270.5 118.5637 -1.1969 140 230 140.1504 0.1074 160 201 160.9522 0.5951 180 178 182.2697 1.2609 200 157 207.1885 3.5943 240 134.5 242.5219 ------- 1.0508 12 200817651 280 114.5 285.5873 1.9955 320 100.5 325.9316 1.8536 360 90.5 362.3912 0.6642 400 81 405.3662 1.3415 440 74.5 441.0851 0.2466 480 68 483.6326 0.7568 本發明之距離量測系統利用一數位相機與一雷射光源 結合’直接利用數位相機所擷取之影像晝面資訊計算待測 ΐ之，離，以達到方便且有效之距離量測，且由以上驗證 二=可=’本發明之系統所量測之結果與實際距離的誤差 二上許範圍之内，因此可保證本發明之準確性。综合 =旦j點，使本發明之距離量測系統可廣泛利用於各種距 輕易利Π’例如交通警察於交通事故發生之後，即可 量測，二協5機同時進行事故現場的拍照存證及距離 、協助曰後進行責任歸屬的釐清。 人士可發:的較佳實施例之後’熟悉該項技術 實施例的實交’且本發明亦不受限於說明書中所舉 13 200817651 【圖式簡單說明】 第一圖為本發明之功能方塊圖； 第二圖為以像素值量測距離的示意圖； 第三圖為數位相機之影像擷取的透視投影圖； 第四圖為計算參數值的計算模型之系統架構圖； 第五圖為驗證畸變差的格線圖 第六圖為數位相機的水平掃描線之灰階值圖； 第七圖為相鄰二垂直格線間之像素值的統計圖； 第八A圖為當办為120公分時之影像圖； 第八B圖為水平掃描線的像素值統計圖， 第九A圖為當/^為440公分時之影像圖；以及 第九B圖為水平掃描線的像素值統計圖。 主要元件符號對照說明： Λ 10—數位相機 20—雷射光源 30…目標物 40-—計算單元 41 —垂直量尺 42—水平重尺 14Threshold = mean{S) + (max(S) - mean(S)) · K where S is the pixel value of the scan line and 夂 is the specific gravity parameter used to calibrate the calculation of the critical value. In the verification step of the present invention, the specific gravity parameter is set to 0.8. According to the critical value, the position of the projected bright spot can be accurately calculated. # ^ After knowing the pixel value (Ab) of the projection point and the scan line center point (zwax/2)' and calculating the parameter value of the digital camera ρχ7 by the calculation model 40 (/^=4.0273 cm, C6^wa ;c=2.8726), the distance between the whiteboard and the digital camera FX7 can be calculated 03⁄4). Reference to the following table is the distance calculated by the system of the present invention and its error: true ^ nd measured & error (%) 60 532.5 58.2466 -2.9223 80 407 77.4490 -3.1888 100 331.5 96.0055 -3.9945 120 270.5 118.5637 - 1.1969 140 230 140.1504 0.1074 160 201 160.9522 0.5951 180 178 182.2697 1.2609 200 157 207.1885 3.5943 240 134.5 242.5219 ------- 1.0508 12 200817651 280 114.5 285.5873 1.9955 320 100.5 325.9316 1.8536 360 90.5 362.3912 0.6642 400 81 405.3662 1.3415 440 74.5 441.0851 0.2466 480 68 483.6326 0.7568 The distance measuring system of the present invention uses a digital camera in combination with a laser light source to directly calculate the distance to be measured by using the image information captured by the digital camera to achieve a convenient and effective distance. The accuracy of the present invention can be ensured by the above test, and the error of the result measured by the system of the present invention and the actual distance is within the range of two. Comprehensive = denier j point, so that the distance measuring system of the present invention can be widely used in various distances and easily profitable 'for example, the traffic police can measure after the traffic accident occurs, and the second joint 5 machine simultaneously carries out the photo deposit of the accident scene. And the distance, assistance, and clarification of the attribution of responsibility. The preferred embodiment of the present invention can be followed by 'familiar with the actual implementation of the technical embodiment' and the present invention is not limited to the description in the specification. 13 200817651 [Simple Description of the Drawing] The first figure is a functional block of the present invention. The second picture is a schematic diagram of measuring the distance by pixel value; the third picture is the perspective projection view of the image captured by the digital camera; the fourth picture is the system architecture diagram of the calculation model for calculating the parameter value; the fifth picture is the verification The sixth diagram of the grid diagram of the distortion is the grayscale value map of the horizontal scan line of the digital camera; the seventh diagram is the statistical diagram of the pixel value between the adjacent two vertical grid lines; the eighth diagram is the 120 cm of the office The image map of the time; the eighth B is a pixel value chart of the horizontal scan line, the ninth A is an image map when /^ is 440 cm; and the ninth B is a pixel value chart of the horizontal scan line. Main component symbol comparison description: Λ 10—digital camera 20—laser light source 30...target object 40-—calculation unit 41—vertical ruler 42—horizontal weight 14