1259740 (1) 玖、發明說明 【發明所屬之技術領域】 本發明是關於一種放電燈點燈裝置及使用該裝置的後 照光裝置。 【先前技術】 具有作爲液晶監測器，液晶電視機等的正下方型後照 光所使用的複數放電燈的放電燈點燈裝置，是使用著如第 6圖及第7圖所示的電路構成。亦即，爲了點亮兩支放電 燈1 a，1 b，串聯連接該兩支放電燈1 a，1 b，使用以一次 繞組2與二次繞組3所構成的兩個電磁變壓器T1，T2， 並將此些電磁變壓器T1，T2的二次繞組3，3的各該低 壓端子彼此間與兩支放電燈1 a，1 b的各該低壓側電極一 起接地，又將各電磁變壓器T1，T2的二次繞組3，3的 各該高壓端子經由連接端子CCFL-1，CCFL-2連接於放電 燈la，lb的各該高壓側電極。又，在各電極變壓T1，T2 的一次繞組2，2連接有構成高頻電源5的一對電晶體5 a ，5b的集極電極。又，來自電磁變壓器ΤΙ，T2的各一次 繞組3，3的高壓端子側連接於放電燈1 a，1 b成爲能輸出 互相地逆相位的電壓。 又，如第8圖所示地，作爲先前的放電燈點燈裝置， 也眾知有爲了簡化接地電路構成，接地兩個電磁變壓器 T 1，T2的二次繞組3，3的低壓端子彼此間，而對於被串 聯連接的放電燈1 a，1 b，其低壓側電極間是僅施以連接 -4- (2) 1259740 而未接地的構成者。又，如第9圖所示地，也眾知代替兩 支放電燈la，lb而採用U型彎曲管10，與表示於第8圖 的放電燈點燈裝置同樣地，接地兩個電磁變壓器T 1，T2 的二次繞組3，3的低壓端子彼此間，並將彎曲管1 0的兩 電極分別連接於二次繞組3，3的各該高壓端子的構成者 〔參照日本特許第 3 293 5 92號（特開 200-3 5 2 7 1 8，第 1 圖至第3圖）公報；特開2001-297613號公報（第1圖） 或是特開平2003-168310公報（第4圖，第7圖）〕。 然而，在此種先前的放電燈點燈裝置中，在各放電燈 的燈電流發生偏差，而排列複數這些放電燈使用作爲正下 方型的後照光時，有在畫面上成爲亮度不均勻的缺點問題 。此種亮度不均勻，是在後照光裝置成爲重大缺點，而被 要求改善。 本發明是鑑於此種先前的技術性課題而創作者，其目 的是在於提供一種對於複數支放電燈點燈成不會產生亮度 不均勻，亦即不會產生亮度偏差的放電燈點燈裝置。 【發明內容】 本發明的一實施例的放電燈點燈裝置，其特徵爲具備 :共通的一次繞組與至少具有第一、第二二次繞組的電磁 變壓器’及在該電磁變壓器的上述第一二次繞組的高壓端 子連接有其中一方的電極的第一冷陰極放電管，及在該第 一冷陰極放電管的另一方的電極連接有其中一方的電極， 而另一方的電極連接於上述電磁變壓器的第二次次繞組的 -5- 1259740 (3) 高壓端子的第二冷陰極放電管’及連接於上述電磁變壓器 的一次繞組的高頻電源電路；分別接地上述電磁變壓器的 第一、第二二次繞組的低壓端子，分別施加互相地相位反 轉的電壓於上述電磁變壓器的第一、第二二次繞組的高壓 端子。 又，上述放電燈點燈裝置中，上述高頻電源電路是具 備射極電極共通地接地，而集極電極分別連接於上述電磁 變壓器的第一、第二二次繞組的高壓端子的一對電晶體元 件；上述電磁變壓器是具備三次繞組；該三次繞組是連接 於上述一對電晶體元件的基極電極，爲其特徵者。 又，依本發明的實施例的後照光裝置，是上述冷陰極 放電燈是排列複數支於共通的反射板上，爲其特徵者。 在如此所構成的放電燈點燈裝置或是包含該點燈裝置 的後照光裝置中，即使在負載的浮遊容量的分布値發生不 平衡於第一、第二二次繞組的高壓側，包含電磁變壓器的 一次繞組的磁性電路也共通之故，因而其中一方的燈電流 變動時另一方也同樣地變動，結果，可維持大約相同的亮 度。 又，依照本發明的放電燈點燈裝置的其他實施例，其 特徵爲具備··共通的一次繞組與至少具有第一、第二二次 繞組的電磁變壓器，及在該電磁變壓器的上述第一二次繞 組的局壓端子連接有其中一方的電極，而另一方的電極連 接於上述電磁變壓器的第二二次繞組的高壓端子的被彎曲 的冷陰極放電燈，及連接於上述電磁變壓器的一次繞組的 -6 - (4) 1259740 局頻電源電路_，分別接地上述電磁變壓器的第一'、第二二 次繞組的低壓端子，分別施加互相地相位反轉的電壓於上 述電磁變壓器的第一、第二二次繞組的高壓端子。 又，在本發明的上述放電燈點燈裝置中，上述高頻電 源電路是形成在設有高電壓高頻輸出凸軌的基板上，連接 有上述彎曲的冷陰極放電燈的電極引出線，爲其特徵者。 又，依本發明的實施例的後照光裝置，是上述彎曲的 冷陰極放電燈是排列複數支於共通的反射板，爲其特徵者 〇 在該放電燈點燈裝置或是後照光裝置中，包含電磁變 壓器的一次繞組的磁性電路爲共通之故，因而藉由彎曲的 冷陰極放電管的各部的浮遊容量的分佈値，在第一二次繞 組欲發生電壓變動，則在第二二次繞組也產生大約同樣的 變動，防止在彎曲的放電管不同部分的燈電流偏差，而在 使用作爲正下方型後照光時，可避免畫面上的亮度不均勻 〇 亦即，本發明人等，檢討了此種正方型後照光裝置發 生亮度不均勻的原因的結果，而找出如下的事實。 一般，如上述的先前裝置所示地在使用複數放電燈的 正下方型後照光裝置中，浮遊容量形成於設在後照光裝置 內的金屬製反射板或是後照光裝置本身的外殼與各放電燈 之間。又，將高頻電力從高頻電源供給於各放電燈的電極 所用的線束與反射板或是後照光裝置本身的外殼等，與放 電燈周圍的環境之間也形成有浮遊容量。又，此些浮遊容 (5) 1259740 量是在每一放電燈藉由此些的位置或是周圍的構造物等的 環境，成爲不相同的容量値。 此種浮遊容量的存在是將以30至60 kHz頻率而超過 1 kV的高頻高壓從高頻電源供給於各放電燈之際，使得 高頻電流的一部分經由這些浮遊容量洩漏。所以，流在放 電燈的管電流按照浮遊容量的大小而每一放電燈地不相同 之故，因而成爲亮度不均勻的原因。 本發明是對於該亮度不均勻的原因，藉由將電磁變壓 器T的一次繞組，俾平均化起因於發生在電磁變壓器τ 的各二次繞組的上述浮遊容量的輸出電流的分佈値，而藉 由將大約同等電流供給於第一及第二冷陰極放電燈1 a， 1 b，作成減少亮度不均勻者。 【實施方式】 以下，依據圖式詳述本發明的實施例。 (第一實施例） 使用第1圖及第2圖說明本發明的第一實施例的放電 燈點燈裝置。本實施例的放電燈點燈裝置，是使用由共通 的一次繞組11與兩個二次繞組1 2 ( 1 )，1 2 ( 2 )，成爲 對於高頻電源電路5的基底繞組的三次繞組1 3所構成的 電磁變壓器T。 爲了點亮兩支放電燈1 a，1 b，串聯連接該兩支放電 燈1 a，1 b的各該低壓側電極，並接地電磁變壓器τ的二 -8- (6) 1259740 次繞組1 2 ( 1 ) ，1 2 ( 2 )的低壓端子彼此間，將電磁變 壓器T的二次繞組12(1) ，：I 2 ( 2 )的各該高壓端子經 由連接端子CCFL-1，CCFL-2連接於放電燈la，lb的各 該高壓側電極。又將電磁變壓器T的一次繞組1 1連接於 高頻電源5，並連接成互相地反轉相位的電壓輸出至各二 次繞組1 2 ( 1 )，1 2 ( 2 )的高壓端子側。 由此在第一實施例的放電燈點燈裝置中，將高頻電源 5連接於電磁變壓器T的共通的一次繞組11，同時從二次 繞組1 2 ( 1 )及二次繞組1 2 ( 2 )發生互相地相位反轉的 高壓波形，藉由將各該高壓波形施加於兩支放電燈1 a， 1 b的各該高壓側電極，俾同時地點亮兩放電燈1 a，1 b。 在此，高頻電源5是具備共通地接地有射極電極，且集極 電極分別連接於上述電磁變壓器的第一、第二二次繞組的 高壓端子的一對電晶體元件5a，5b。上述電磁變壓器是 具備三次繞組；該三次繞組是連接於上述一對電晶體元件 5a，5b的基極電極。在該一對電晶體元件5a，5b的基極 電極與集極電極間，從直流電源端子5 d供給有偏壓。又 ’在一對電晶體元件5 a，5 b的集極電極間連接有電磁變 壓器T的電感成分以及決定振盪頻率的電容器5c。高頻 電源5是構成電磁變壓器T及振盪器的所謂反相電路。 如弟1圖所不地’在點売該放電燈1 a，1 b時，互相 地相位反轉的高頻電壓施加於兩放電燈1 a，1 b的高壓側 電極。以負載的浮遊容量的分佈値擬在二次繞組12(1) ’ 1 2 ( 2 )的高壓側產生不平衡時，則因電磁變壓器τ的 -9- (7) 1259740 磁性電路爲共通，若其中一方的燈電流有變動，則另一方 也同樣地變動，結果，放電燈1 a，1 b是可維持大約相同 的亮度。 詳述該動作，作爲負載於電磁變壓器T的二次繞組 12(1) ，：12(2)所連接的放電燈la，lb本身的容量及 產生在這些的浮遊容量，是對於高頻電源5的頻率F有影 響。例如附隨於放電燈1 a，1 b的浮遊容量變大，貝U F 〇cl /( LC ) 1/2之故，因而降低高頻電源5的頻率。在此，L 是電磁變壓器T的電感；C是高頻電源5的電容器5c的 容量。結果，依據電磁變壓器T的電感L成分，阻抗也 降低之故，因而輸出至電磁變壓器T的二次繞組1 2 ( 1 ) ，1 2 ( 2 )的高頻電流會增加。該高頻電流的增加是作用 於能彌補經由浮遊容量而因洩漏高頻電流所減少的放電燈 1 a，1 b的管電流。 亦即，在該放電燈點燈裝置中，起因於產生在連接於 電磁變壓器T的第一二次繞組12(1)的第一冷陰極放電 燈1 a的浮遊容量的燈電流的變動，是變更電磁變壓器T 內的電感成分的壓降，而在電磁變壓器T的第一二次繞組 12(1)，供給有能抵銷該變動的電流。在連接於電磁變 壓器T的第二二次繞組1 2 ( 2 )的第二冷陰極放電燈1 b， 也產生起因於其浮遊容量的燈電流變動，同樣地，藉由電 磁變壓器T內的電感L成分，供給有能抵銷該變動的電 流。但是，電磁變壓器T是其一次繞組Π爲共通之故， 因而在第一、第二二次繞組1 2 ( 1 )，1 2 ( 2 )供給有經 •10- 1259740 (8) 平均化的大約同樣大小的電流。結果，第一、第二冷陰極 放電燈1 a，1 b是成爲以大約相同電流相同的亮度被點亮 ，可避免亮度不均勻。 又雖未圖示，在第1圖，電磁變壓器T及連接於該二 次側的兩支放電燈1 a，1 b所構成的組合是設置複數組， 此些複數組放電燈1 a，1 b是排列於共通的金屬製反射板 上’與上述的放電燈點燈裝置一起被收納在後照光裝置用 的外殼內。 因此，將本實施例的放電燈點燈裝置使用作爲正下方 型後照光等，可避免在畫面上發生亮度不均勻，可得到均 句売度的照明。 (第二實施例） 以下，使用第3圖說明本發明的第二實施例的放電燈 點燈裝置。第二實施例的放電燈點燈裝置是電磁變壓器T 的構成與第一實施例同樣。又，作爲放電燈使用U形彎 曲管10，將其兩端的電極連接於輸出電磁變壓器T的互 相地相位反轉的高電壓高頻的二次繞組12(1) »12(2 )的各該高壓側端子。 在該第二實施例的放電燈點燈裝置中，在電磁變壓器 T的共通一次繞組1 1藉由連接高頻電源5，從第一二次繞 組1 2 ( 1 )發生高壓波形，而從第二二次繞組1 2 ( 2 )發 生經反轉相位的高頻電壓。此些高頻電壓是分別施加於彎 曲管10的兩電極，使得彎曲管10被放電點亮。 -11 - (9) 1259740 如第3圖所示地，在點亮該彎曲管i 〇時，互相地相 位反轉的高頻電壓施加於兩電極，即使以U形彎曲管1 0 的互相地平行的直管部分的浮遊容量的分佈値而在二次繞 組1 2 ( 1 )，1 2 ( 2 )的高壓側產生不平衡，電磁變壓器T 的破性電路爲共通之故’因而如在第一'實施例所說明，若 其中一方的燈電流變動，則另一方也同樣地變動，而可將 彎曲管1 〇兩側的亮度維持在相同。因此，即使將本實施 例的放電燈點燈裝置使用作爲正下方型的後照光時，也不 會在畫面上發生亮度不均勻，而可進行均勻亮度的照相。 又，彎曲管放電燈1 0的電源電路側對於輸出電極的 連接構造，是作成第4圖的構造較理想。在該第4圖中， 2 1是收容於放電燈點燈裝置的電源裝置的框體的基板， 而在該基板21的高電壓高頻輸出部設置凸軌22(1)， 22(2)。另一方面，引出線23(1) ，23(2)從彎曲管 放電燈1〇的兩電極朝相同方向拉出。又，在彎曲管放電 燈1 〇對於電源裝置的連接時，對於框體2 1的凸軌2 2 ( 1 )，2 2 ( 2 )以如錫焊的方法分別連接彎曲管放電燈1 〇的 兩引出線23 ( 1 )，23 ( 2 )，而儘量不使用電線束。 由此，對於利用如第5圖所示的電線束2 4的連接構 成，可提高電力的傳動效率。亦即，不存在電線束2 4及 包含於後照光裝置的反射板或外殼之間的浮遊容量之故， 因而經由此些浮遊容量不會從電線束2 4流動洩漏電流。 所以，可抑制利用電線束周邊的浮遊容量的相差所產生的 放電燈1 〇的電極間的點燈電流値的相差，而可防止亮度 •12- 1259740 (10) 不均勻。又，可刪減電線束24、外罩25、連接器26、絕 緣管27等零件，因而也可降低成本。 又，在第3圖、第4圖雖未圖示，惟電磁變壓器T及 連接於該二次側的彎曲的放電燈1 0所構成的組合，是設 置複數組，而此些複數組放電燈1 〇是排列在共通的金屬 製反射板上，而與上述的放電燈點燈裝置一起被收納在後 照光裝置用的外殼內，而被使用作爲正下方型後照光裝置 〇 本發明是並不被限定於以上所說明的實施例者，而可 做各種變形。 例如構成表示於第2圖的高頻電源5的電晶體元件 5a，5b是MOS電晶體來代替雙極性電晶體也可以。這時 候，雙極性電晶體的各畫素，射極，集極及基極是分別指 MOS電晶體的源極、汲極及閘極者。 又，表示於第3圖及第4圖的彎曲管放電燈1〇是並 不一定形成U形狀者。 又’本發明是並不被限定於正下方型後照光裝置，也 可適用於將光源配置在導光板的邊緣的所謂邊緣型後照光 裝置。 【圖式簡單說明】 第1圖是表示本發明的第一實施例的放電燈點燈裝置 的方塊圖。 第2圖是表示圖示於第1圖的放電燈點燈裝置的電路 -13- (11) 1259740 圖。 第3圖是表示本發明的第二實施例的放電燈點燈裝置 的方塊圖。 第4圖是表示本發明的第二實施例的彎曲管放電燈對 於電源裝置框體的連接構造的俯視圖。 第5圖是表示使用本發明的第二實施例的彎曲管放電 ;燈與電、源裝置框體之間的電線束的連接構造的俯視圖。 第6圖是表示先前例的放電燈點燈裝置的方塊圖。 第7圖是表示圖示於第6圖的先前放電燈點燈裝置的 電路圖。 第8圖是表示先前的其他放電燈點燈裝置的方塊圖。 第9圖是表示先前的另一放電燈點燈裝置的方塊圖。 主要元件對照^ 1 a , 1 b :放電燈 2 , 1 1 · * 次繞組 3 , 12(1) 5 12(2):二次繞組 5 :高頻電源 5a，5b :電晶體元件 10 :彎曲管 1 3 :三次繞不且 5 e :電容器 2 1 :基板 2?(1) ，22(2):凸軌 -14- (12) (12)1259740 23(1) ， 23 ( 2):引出線 2 4 :電線束 2 5 :外罩 2 6 :連接器 2 7 :絕緣管 T :電磁變壓器 CCFL-1，CCFL-2 ：連接端子1259740 (1) Field of the Invention The present invention relates to a discharge lamp lighting device and a backlight device using the same. [Prior Art] A discharge lamp lighting device having a plurality of discharge lamps used as a liquid crystal monitor, a liquid crystal television, or the like, is a circuit configuration as shown in Figs. 6 and 7. That is, in order to illuminate the two discharge lamps 1 a, 1 b, the two discharge lamps 1 a, 1 b are connected in series, and two electromagnetic transformers T1, T2 composed of the primary winding 2 and the secondary winding 3 are used. And the low voltage terminals of the secondary windings 3, 3 of the electromagnetic transformers T1, T2 are grounded together with the low voltage side electrodes of the two discharge lamps 1 a, 1 b, and the electromagnetic transformers T1, T2 are further connected. Each of the high voltage terminals of the secondary windings 3, 3 is connected to each of the high voltage side electrodes of the discharge lamps 1a, 1b via connection terminals CCFL-1, CCFL-2. Further, collector electrodes of a pair of transistors 5a and 5b constituting the high-frequency power source 5 are connected to the primary windings 2, 2 of the respective electrode transformation voltages T1 and T2. Further, the high voltage terminal side of each of the primary windings 3, 3 from the electromagnetic transformer ΤΙ, T2 is connected to the discharge lamp 1a, and 1b is a voltage capable of outputting mutually opposite phases. Further, as shown in Fig. 8, as a conventional discharge lamp lighting device, it is also known to ground the low voltage terminals of the secondary windings 3, 3 of the two electromagnetic transformers T1, T2 in order to simplify the grounding circuit configuration. For the discharge lamps 1 a, 1 b connected in series, the low-voltage side electrodes are only connected to the -4- (2) 1259740 and are not grounded. Further, as shown in Fig. 9, it is also known that the U-shaped bending tube 10 is used instead of the two discharge lamps 1a and 1b, and the two electromagnetic transformers T are grounded similarly to the discharge lamp lighting device shown in Fig. 8. 1, the low voltage terminals of the secondary windings 3, 3 of T2 are mutually connected, and the two electrodes of the bending tube 10 are respectively connected to the constituents of the high voltage terminals of the secondary windings 3, 3 [refer to Japanese Patent No. 3 293 5 Bulletin No. 92 (JP-200-3 5 2 7 1 8, Figure 1 to Figure 3); JP-A-2001-297613 (Fig. 1) or JP-A-2003-168310 (Fig. 4, 7))). However, in such a conventional discharge lamp lighting device, when the lamp current of each discharge lamp is deviated, and the plurality of discharge lamps are arranged as a direct-back type backlight, there is a disadvantage that brightness is uneven on the screen. problem. Such uneven brightness is a major drawback in the backlight device and is required to be improved. The present invention has been made in view of such a prior art problem, and it is an object of the invention to provide a discharge lamp lighting device which does not cause unevenness in brightness, i.e., does not cause a variation in luminance, for a plurality of discharge lamps. SUMMARY OF THE INVENTION A discharge lamp lighting device according to an embodiment of the present invention includes: a common primary winding and an electromagnetic transformer having at least first and second secondary windings; and the first of the electromagnetic transformers a first cold cathode discharge tube having one of the electrodes connected to the high voltage terminal of the secondary winding, and one of the electrodes connected to the other of the first cold cathode discharge tube, and the other electrode is connected to the electromagnetic a second cold cathode discharge tube of the second secondary winding of the transformer - 5 - 1259740 (3) a high voltage terminal and a high frequency power supply circuit connected to the primary winding of the electromagnetic transformer; respectively, grounding the first and the first of the electromagnetic transformer The low-voltage terminals of the secondary windings are respectively applied with voltages that are phase-reversed with each other to the high-voltage terminals of the first and second secondary windings of the electromagnetic transformer. Further, in the discharge lamp lighting device, the high-frequency power supply circuit is provided with a pair of electrodes in which the emitter electrodes are commonly grounded, and the collector electrodes are respectively connected to the high-voltage terminals of the first and second secondary windings of the electromagnetic transformer. The crystal element; the electromagnetic transformer is provided with a tertiary winding; the tertiary winding is a base electrode connected to the pair of transistor elements, and is characterized by the same. Further, in the backlight device according to the embodiment of the present invention, the cold cathode discharge lamp is characterized in that a plurality of common reflection plates are arranged. In the discharge lamp lighting device configured as described above or the backlight device including the lighting device, even if the distribution of the floating capacity of the load is unbalanced on the high voltage side of the first and second secondary windings, the electromagnetic field is included. The magnetic circuit of the primary winding of the transformer is also common, so that the other one of the lamp currents fluctuates in the same manner, and as a result, approximately the same brightness can be maintained. Further, another embodiment of the discharge lamp lighting device according to the present invention is characterized by comprising: a common primary winding and an electromagnetic transformer having at least first and second secondary windings, and the first of the electromagnetic transformers a bent cold cathode discharge lamp in which a voltage of one of the secondary windings is connected to one of the electrodes, and the other electrode is connected to a high voltage terminal of the second secondary winding of the electromagnetic transformer, and one time connected to the electromagnetic transformer Winding -6 - (4) 1259740 local frequency power supply circuit _, respectively grounded to the low voltage terminals of the first and second secondary windings of the electromagnetic transformer, respectively, respectively applying a phase reversal voltage to the first of the electromagnetic transformer The high voltage terminal of the second secondary winding. Further, in the above-described discharge lamp lighting device of the present invention, the high-frequency power supply circuit is formed on a substrate provided with a high-voltage high-frequency output bump, and an electrode lead wire of the curved cold cathode discharge lamp is connected thereto. Its characteristics. Moreover, according to the backlight device of the embodiment of the present invention, the curved cold cathode discharge lamp is arranged in a plurality of common reflecting plates, and is characterized in that the discharge lamp lighting device or the backlight device is The magnetic circuit including the primary winding of the electromagnetic transformer is common, and therefore, by the distribution of the floating capacity of each portion of the curved cold cathode discharge tube, the voltage is changed in the first secondary winding, and the second secondary winding is The same variation is also generated to prevent variations in the lamp current in different portions of the curved discharge tube, and when the backlight is used as the direct type, the brightness unevenness on the screen can be avoided, that is, the inventors reviewed As a result of the uneven brightness of the square rear light illumination device, the following facts were found. In general, as shown in the above prior apparatus, in a direct-type backlight device using a plurality of discharge lamps, the floating capacity is formed in a metal reflector provided in the backlight device or a casing and a discharge of the backlight device itself. Between the lights. Further, the high-frequency power is supplied from the high-frequency power source to the wire harness used for the electrodes of the respective discharge lamps, the reflector or the outer casing of the backlight unit itself, and the like, and a floating capacity is formed between the surroundings of the discharge lamp. Moreover, the amount of the floating volume (5) 1259740 is a different capacity 在 in the environment of each of the discharge lamps by such a position or a surrounding structure. Such a floating capacity exists when a high-frequency high voltage exceeding 1 kV at a frequency of 30 to 60 kHz is supplied from a high-frequency power source to each discharge lamp, so that a part of the high-frequency current leaks through these floating capacities. Therefore, the tube current flowing through the discharge lamp is different for each discharge lamp in accordance with the size of the floating capacity, and thus causes uneven brightness. The present invention is directed to the unevenness of the luminance, by averaging the primary winding of the electromagnetic transformer T by the distribution of the output current of the floating capacity occurring in each secondary winding of the electromagnetic transformer τ. An approximately equal current is supplied to the first and second cold cathode discharge lamps 1a, 1b to reduce unevenness in brightness. [Embodiment] Hereinafter, embodiments of the present invention will be described in detail based on the drawings. (First Embodiment) A discharge lamp lighting device according to a first embodiment of the present invention will be described with reference to Figs. 1 and 2 . The discharge lamp lighting device of the present embodiment uses the common primary winding 11 and the two secondary windings 1 2 ( 1 ), 1 2 ( 2 ) to become the tertiary winding 1 for the base winding of the high-frequency power supply circuit 5 3 electromagnetic transformer T. In order to illuminate the two discharge lamps 1 a, 1 b , the low-voltage side electrodes of the two discharge lamps 1 a, 1 b are connected in series, and the two-8-(6) 1259740 secondary windings of the electromagnetic transformer τ are grounded. (1), the low voltage terminals of 1 2 (2) are connected to each other, and the high voltage terminals of the secondary windings 12(1), I2(2) of the electromagnetic transformer T are connected via the connection terminals CCFL-1, CCFL-2 Each of the high voltage side electrodes of the discharge lamps la, lb. Further, the primary winding 1 1 of the electromagnetic transformer T is connected to the high-frequency power source 5, and the voltages which are connected to each other to reverse the phase are output to the high-voltage terminal side of each of the secondary windings 1 2 ( 1 ), 1 2 ( 2 ). Thus, in the discharge lamp lighting device of the first embodiment, the high-frequency power source 5 is connected to the common primary winding 11 of the electromagnetic transformer T while the secondary winding 1 2 ( 1 ) and the secondary winding 1 2 ( 2 The high-voltage waveforms in which the phases are reversed in phase are applied to each of the high-voltage side electrodes of the two discharge lamps 1a, 1b by the respective high-voltage waveforms, and the two discharge lamps 1a, 1b are simultaneously illuminated. Here, the high-frequency power source 5 is a pair of transistor elements 5a, 5b including a high-voltage terminal in which the collector electrodes are commonly connected to the emitter electrodes and the collector electrodes are respectively connected to the first and second secondary windings of the electromagnetic transformer. The electromagnetic transformer described above is provided with a tertiary winding; the tertiary winding is a base electrode connected to the pair of transistor elements 5a, 5b. A bias voltage is supplied from the DC power source terminal 5d between the base electrode and the collector electrode of the pair of transistor elements 5a, 5b. Further, an inductance component of the electromagnetic transformer T and a capacitor 5c for determining an oscillation frequency are connected between the collector electrodes of the pair of transistor elements 5a, 5b. The high frequency power source 5 is a so-called inverter circuit constituting the electromagnetic transformer T and the oscillator. When the discharge lamps 1 a, 1 b are turned on, the high-frequency voltages which are mutually inverted in phase are applied to the high-voltage side electrodes of the two discharge lamps 1 a, 1 b. When the distribution of the floating capacity of the load is simulated to be unbalanced on the high voltage side of the secondary winding 12(1) ' 1 2 ( 2 ), the magnetic circuit of the electromagnetic transformer τ is common to the -9-(7) 1259740 magnetic circuit. When the lamp current of one of them changes, the other one also changes in the same manner. As a result, the discharge lamps 1a, 1b can maintain approximately the same brightness. This operation is described in detail as the discharge lamp la (1) of the electromagnetic transformer T, the discharge lamp la connected to the 12 (2), the capacity of the lb itself, and the floating capacity generated therein, for the high frequency power supply 5 The frequency F has an effect. For example, the floating capacity accompanying the discharge lamps 1 a, 1 b becomes large, and the U F 〇cl /( LC ) 1/2 is reduced, thereby reducing the frequency of the high-frequency power source 5. Here, L is the inductance of the electromagnetic transformer T; C is the capacity of the capacitor 5c of the high-frequency power source 5. As a result, the impedance is also lowered in accordance with the inductance L component of the electromagnetic transformer T, so that the high-frequency current output to the secondary windings 1 2 ( 1 ) and 1 2 ( 2 ) of the electromagnetic transformer T increases. This increase in the high-frequency current is applied to the tube current that can compensate for the discharge lamp 1 a, 1 b which is reduced by the leakage of the high-frequency current via the floating capacity. That is, in the discharge lamp lighting device, the fluctuation of the lamp current due to the floating capacity of the first cold cathode discharge lamp 1 a connected to the first secondary winding 12 (1) of the electromagnetic transformer T is The voltage drop of the inductance component in the electromagnetic transformer T is changed, and a current that can cancel the fluctuation is supplied to the first secondary winding 12 (1) of the electromagnetic transformer T. The second cold cathode discharge lamp 1 b connected to the second secondary winding 1 2 ( 2 ) of the electromagnetic transformer T also generates a lamp current variation due to its floating capacity, and similarly, the inductance in the electromagnetic transformer T The L component is supplied with a current that can offset the fluctuation. However, the electromagnetic transformer T is common to its primary winding turns, so that the first and second secondary windings 1 2 ( 1 ), 1 2 ( 2 ) are supplied with an average of about 10 - 1259740 (8). The same amount of current. As a result, the first and second cold cathode discharge lamps 1 a, 1 b are lit with the same brightness at about the same current, and luminance unevenness can be avoided. Further, although not shown, in Fig. 1, the combination of the electromagnetic transformer T and the two discharge lamps 1a, 1b connected to the secondary side is a set of complex arrays, and these multiple array discharge lamps 1 a, 1 b is arranged on a common metal reflector, and is housed in the casing for the backlight unit together with the above-described discharge lamp lighting device. Therefore, the discharge lamp lighting device of the present embodiment can be used as a direct-back type backlight or the like, thereby avoiding uneven brightness on the screen and obtaining uniform illumination. (Second embodiment) Hereinafter, a discharge lamp lighting device according to a second embodiment of the present invention will be described using FIG. The discharge lamp lighting device of the second embodiment has the same configuration as that of the first embodiment of the electromagnetic transformer T. Further, the U-shaped bent tube 10 is used as a discharge lamp, and the electrodes at both ends thereof are connected to the high-voltage high-frequency secondary windings 12(1) » 12(2) of the output electromagnetic transformer T which are mutually phase-reversed. High voltage side terminal. In the discharge lamp lighting device of the second embodiment, the common primary winding 1 of the electromagnetic transformer T generates a high voltage waveform from the first secondary winding 1 2 ( 1 ) by connecting the high frequency power source 5, and The secondary winding 1 2 ( 2 ) generates a high frequency voltage of the reversed phase. These high frequency voltages are respectively applied to the two electrodes of the curved tube 10, so that the bending tube 10 is discharged by the discharge. -11 - (9) 1259740 As shown in Fig. 3, when the bending tube i 点亮 is lit, high-frequency voltages which are mutually inverted in phase are applied to the two electrodes even if the U-shaped curved tubes 10 are mutually The distribution of the floating capacity of the parallel straight pipe portion is unbalanced on the high voltage side of the secondary winding 1 2 ( 1 ), 1 2 ( 2 ), and the breaking circuit of the electromagnetic transformer T is common. As described in the 'Example, if one of the lamp currents fluctuates, the other one also changes in the same manner, and the brightness of both sides of the curved tube 1 维持 can be maintained the same. Therefore, even when the discharge lamp lighting device of the present embodiment is used as the backlight of the direct type, no unevenness in brightness occurs on the screen, and photographing with uniform brightness can be performed. Further, the connection structure of the power supply circuit side of the curved tube discharge lamp 10 to the output electrode is preferably the structure shown in Fig. 4. In the fourth drawing, 21 is a substrate of a casing housed in a power supply device of the discharge lamp lighting device, and a convex rail 22 (1), 22 (2) is provided at a high-voltage high-frequency output portion of the substrate 21. . On the other hand, the lead wires 23(1), 23(2) are pulled out from the two electrodes of the curved tube discharge lamp 1〇 in the same direction. Moreover, when the bending tube discharge lamp 1 is connected to the power supply device, the convex rails 2 2 ( 1 ), 2 2 ( 2 ) of the frame 2 1 are respectively connected to the bending tube discharge lamp 1 by soldering. Take two leads 23 ( 1 ), 23 ( 2 ) and try not to use the wiring harness. Thereby, with the connection configuration of the electric wire bundle 24 as shown in Fig. 5, the transmission efficiency of electric power can be improved. That is, there is no floating capacity between the electric wire bundle 24 and the reflecting plate or the outer casing included in the backlight unit, so that leakage current does not flow from the electric wire bundle 24 via these floating capacities. Therefore, it is possible to suppress the phase difference of the lighting current 电极 between the electrodes of the discharge lamp 1 产生 which is caused by the phase difference of the floating capacity around the electric wire bundle, and to prevent the unevenness of the brightness • 12-1259740 (10). Further, parts such as the electric wire bundle 24, the outer cover 25, the connector 26, and the insulating tube 27 can be eliminated, so that the cost can be reduced. Further, although not shown in FIGS. 3 and 4, the combination of the electromagnetic transformer T and the curved discharge lamp 10 connected to the secondary side is a complex array, and these complex array discharge lamps are provided. 1 〇 is arranged on a common metal reflector, and is housed in a casing for a backlight device together with the above-described discharge lamp lighting device, and is used as a direct-down type backlight device. It is limited to the embodiments described above, and various modifications can be made. For example, the transistor elements 5a and 5b constituting the high-frequency power source 5 shown in Fig. 2 may be MOS transistors instead of the bipolar transistors. At this time, the pixels, emitters, collectors, and bases of the bipolar transistor refer to the source, drain, and gate of the MOS transistor, respectively. Further, the curved tube discharge lamps 1A shown in Figs. 3 and 4 are not necessarily U-shaped. Further, the present invention is not limited to the direct type rear backlight device, and is also applicable to a so-called edge type rear illumination device in which a light source is disposed at the edge of the light guide plate. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a block diagram showing a discharge lamp lighting apparatus according to a first embodiment of the present invention. Fig. 2 is a view showing a circuit -13-(11) 1259740 of the discharge lamp lighting device shown in Fig. 1. Fig. 3 is a block diagram showing a discharge lamp lighting device of a second embodiment of the present invention. Fig. 4 is a plan view showing a connection structure of a bending tube discharge lamp according to a second embodiment of the present invention with respect to a power supply unit casing. Fig. 5 is a plan view showing a connection structure of a wire bundle between the lamp and the electric and source device casing using the bending tube discharge of the second embodiment of the present invention. Fig. 6 is a block diagram showing a discharge lamp lighting device of the prior art. Fig. 7 is a circuit diagram showing a prior discharge lamp lighting device shown in Fig. 6. Fig. 8 is a block diagram showing another conventional discharge lamp lighting device. Fig. 9 is a block diagram showing another discharge lamp lighting device of the prior art. Main component control ^ 1 a , 1 b : discharge lamp 2 , 1 1 · * secondary winding 3 , 12 (1) 5 12 (2): secondary winding 5 : high frequency power supply 5a, 5b : transistor element 10 : bending Tube 1 3 : Triple winding and 5 e : Capacitor 2 1 : Substrate 2?(1), 22(2): Convex rail-14- (12) (12) 1259740 23(1), 23 ( 2): Lead out Line 2 4 : Wiring harness 2 5 : Housing 2 6 : Connector 2 7 : Insulation tube T : Electromagnetic transformer CCFL-1, CCFL-2 : Connection terminal
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