TWI835710B

TWI835710B - Zoom lens

Info

Publication number: TWI835710B
Application number: TW106120578A
Authority: TW
Inventors: 洪偉智; 林信忠; 王欣仁
Original assignee: 光芒光學股份有限公司
Priority date: 2017-06-20
Filing date: 2017-06-20
Publication date: 2024-03-21
Also published as: TW201905534A

Abstract

A zoom lens includes a zooming lens group, a focusing lens group and a photo interrupter. The photo interrupter is used to detect the position of the zooming lens group and the focusing lens group. The photo interrupter includes a light emitting element and a light receiving element that form a light transmission path. A peak wavelength of light beams emitted from the light emitting element is larger than 860nm.

Description

變焦鏡頭 zoom lens

本發明關於一種變焦鏡頭。 The present invention relates to a zoom lens.

使用具變焦鏡頭的相機讓使用者可以依據自身需求來調整焦距，目前已相當普及。變焦鏡頭內可設置光遮斷器，光遮斷器可偵測遮光狀態和無遮光狀態的變化確認變焦鏡頭內的可動鏡組的位置。然而，光遮斷器於致動時發出的紅外光，會於影像感測器上成像而構成俗稱鬼影的雜訊影像，影響畫面品質。一習知做法為將光遮斷器置放於端點，再利用機構件去遮蔽紅外光以減少鬼影，但該作法無法大幅度地減少或完全避免鬼影產生。 Cameras with zoom lenses allow users to adjust the focal length according to their needs, which is now quite popular. A light interrupter can be set in the zoom lens. The light interrupter can detect the change between the light-shielded state and the light-unshielded state to confirm the position of the movable lens group in the zoom lens. However, the infrared light emitted by the light interrupter when activated will form an image on the image sensor to form a noise image commonly known as ghosting, which affects the picture quality. A common practice is to place the light interrupter at the end point and then use a mechanism to block the infrared light to reduce ghosting, but this method cannot significantly reduce or completely avoid the occurrence of ghosting.

本發明的其他目的和優點可以從本發明實施例所揭露的技術特徵中得到進一步的瞭解。 Other purposes and advantages of the present invention can be further understood from the technical features disclosed in the embodiments of the present invention.

本發明一實施例提出一種變焦鏡頭，包含一變焦鏡組、一對焦鏡組以及一光遮斷器。光遮斷器用以偵測變焦鏡組或對焦鏡組的位置，光遮斷器包含可形成一光通路的一發光元件及一受光元件，且發光元件發出的光束的峰值波長大於860nm。於一較佳範圍，發光元件發出的光束的峰值波長可大於890nm。於一更佳範圍，發光元件發出的光束的峰值波長可大於950nm。 An embodiment of the present invention provides a zoom lens, which includes a zoom lens group, a focusing lens group and a photointerrupter. The photointerrupter is used to detect the position of the zoom lens group or the focus lens group. The photointerrupter includes a light-emitting element and a light-receiving element that can form a light path, and the peak wavelength of the light beam emitted by the light-emitting element is greater than 860nm. In a preferred range, the peak wavelength of the light beam emitted by the light-emitting element can be greater than 890 nm. In a better range, the peak wavelength of the light beam emitted by the light-emitting element can be greater than 950 nm.

本發明一實施例提出一種變焦鏡頭，變焦鏡頭用於具有一影像感測器的一取像裝置且包含一變焦鏡組、一對焦鏡組以及一光遮斷器。光遮斷器用以偵測變焦鏡組或對焦鏡組的位置，且光遮斷器發出之光束的峰值波長位於影像感測器的一感應波長範圍外。若影像感測器對該光束的光學響應在峰值時的量子效率定為100%，則感應波長範圍係對應大於15%的量子效率的波長範圍。 An embodiment of the present invention provides a zoom lens. The zoom lens is used in an imaging device with an image sensor and includes a zoom lens group, a focusing lens group and a photointerrupter. The photointerrupter is used to detect the position of the zoom lens group or the focusing lens group, and the peak wavelength of the light beam emitted by the photointerrupter is outside a sensing wavelength range of the image sensor. If the quantum efficiency of the image sensor's optical response to the light beam at the peak is set to be 100%, then the sensing wavelength range corresponds to a wavelength range with a quantum efficiency greater than 15%.

本發明另一實施例提出一種變焦鏡頭，包含一變焦鏡組、一對焦鏡組、一第一光遮斷器及一第二光遮斷器。第一光遮斷器用以偵測變焦鏡組的位置且具有一第一電路，第二光遮斷器用以偵測對焦鏡組的位置且具有一第二電路，且第一電路與第二電路可分別獨立運作。 Another embodiment of the present invention provides a zoom lens, comprising a zoom lens unit, a focus lens unit, a first light interrupter and a second light interrupter. The first light interrupter is used to detect the position of the zoom lens unit and has a first circuit, the second light interrupter is used to detect the position of the focus lens unit and has a second circuit, and the first circuit and the second circuit can operate independently.

本發明另一實施例提出一種變焦鏡頭，包含一變焦鏡組、一對焦鏡組、一第一光遮斷器及一第二光遮斷器。變焦鏡組和對焦鏡組可於一光軸上移動以分別進行變焦及對焦操作。第一光遮斷器用以偵測變焦鏡組的位置，第二光遮斷器用以偵測對焦鏡組的位置，且第二光遮斷器於第一光遮斷器作動時關閉。 Another embodiment of the present invention provides a zoom lens, including a zoom lens group, a focusing lens group, a first photointerrupter and a second photointerrupter. The zoom lens group and the focus lens group can move on an optical axis to perform zoom and focus operations respectively. The first photointerrupter is used to detect the position of the zoom lens group, the second photointerrupter is used to detect the position of the focusing lens group, and the second photointerrupter is closed when the first photointerrupter is activated.

藉由本發明各個實施例的設計，因光遮斷器發出之光束的峰值波長位於影像感測器的一感應波長範圍外，影像感測器不會對光遮斷器發出的光線成像而可避免鬼影產生。再者，因可分別獨立運作第一光遮斷器及第二光遮斷器，故可交替作動第一光遮斷器與第二光遮斷器、或可視變焦鏡頭的實際調焦方式決定第一光遮斷器與第二光遮斷器的開閉時序，藉以有效減少或完全避免鬼影產生。 By designing each embodiment of the present invention, since the peak wavelength of the light beam emitted by the light interrupter is outside a sensing wavelength range of the image sensor, the image sensor will not form an image of the light emitted by the light interrupter, thereby avoiding the generation of ghost images. Furthermore, since the first light interrupter and the second light interrupter can be operated independently, the first light interrupter and the second light interrupter can be operated alternately, or the actual focusing method of the visual zoom lens determines the opening and closing timing of the first light interrupter and the second light interrupter, thereby effectively reducing or completely avoiding the generation of ghost images.

本發明的其他目的和優點可以從本發明所揭露的技術特徵中得到進一步的瞭解。為讓本發明之上述和其他目的、特徵和優點能更明顯易懂，下文特舉實施例並配合所附圖式，作詳細說明如下。 Other objects and advantages of the present invention can be further understood from the technical features disclosed in the present invention. In order to make the above and other objects, features and advantages of the present invention more obvious and understandable, the following embodiments are described in detail with reference to the accompanying drawings.

1‧‧‧取像裝置 1‧‧‧Imaging device

2‧‧‧光軸 2. Optical axis

3‧‧‧濾光片 3‧‧‧Filter

4‧‧‧影像感測器 4. Image sensor

10‧‧‧變焦鏡頭 10. Zoom lens

12‧‧‧變焦鏡組 12‧‧‧Zoom lens set

14‧‧‧對焦鏡組 14‧‧‧Focusing lens set

16‧‧‧第一光遮斷器 16‧‧‧First photointerrupter

18‧‧‧第二光遮斷器 18. Second photointerrupter

20‧‧‧變焦鏡頭 20‧‧‧zoom lens

22、24‧‧‧驅動機件 22, 24. Driving parts

222、242‧‧‧遮光部 222, 242‧‧‧Shade

G1‧‧‧第一鏡組 G1‧‧‧First lens group

G2‧‧‧第二鏡組 G2‧‧‧Second lens group

G3‧‧‧第三鏡組 G3‧‧‧Third lens group

G4‧‧‧第四鏡組 G4‧‧‧Fourth lens group

G5‧‧‧第五鏡組 G5‧‧‧Fifth lens group

圖1顯示本發明一實施例之變焦鏡頭的示意圖。 FIG. 1 shows a schematic diagram of a zoom lens according to an embodiment of the present invention.

圖2顯示一光遮斷器的發光元件及受光元件的光譜分佈曲線。 Figure 2 shows the spectral distribution curve of the light-emitting element and the light-receiving element of a photointerrupter.

圖3顯示一影像感測器的光學響應圖。 FIG3 shows an optical response diagram of an image sensor.

圖4顯示本發明另一實施例之變焦鏡頭的示意簡圖。 FIG. 4 shows a schematic diagram of a zoom lens according to another embodiment of the present invention.

圖5顯示圖4的變焦鏡頭的剖面示意圖。 FIG. 5 is a schematic cross-sectional view of the zoom lens of FIG. 4 .

有關本發明之前述及其他技術內容、特點與功效，在以下配合參考圖式之實施例的詳細說明中，將可清楚的呈現。以下實施例中所提到的方向用語，例如：上、下、左、右、前或後等，僅是參考附加圖式的方向。因此，使用的方向用語是用來說明並非用來限制本發明。 The aforementioned and other technical contents, features and effects of the present invention will be clearly presented in the following detailed description of the embodiments with reference to the drawings. Directional terms mentioned in the following embodiments, such as up, down, left, right, front or back, etc., are only for reference to the directions in the attached drawings. Accordingly, the directional terms used are illustrative and not limiting of the invention.

圖1顯示本發明一實施例之變焦鏡頭的示意圖。如圖1所示，變焦鏡頭10具有一變焦鏡組(zooming lens group)12、一對焦鏡組(focusing lens group)14、一第一光遮斷器16及一第二光遮斷器18。於一典型的光遮斷器中，具有可形成一光通路的發光元件及受光元件，發光元件及受光元件之間具有一空氣間隙，若此間隙中沒有物體阻擋，發光元件發出的光線會直接照射受光元件；反之若間隙中有物體阻擋光線，則受光元件將無光線照射而改變輸出狀態。因此，第一光遮斷器16可藉由偵測遮光狀態和無遮光狀態的變化確認變焦鏡組12的位置，且第二光遮斷器18可藉由偵測遮光狀態和無遮光狀態的變化確認對焦鏡組14的位置。於本實施例中，第一光遮斷器16及第二光遮斷器18的發光元件(未圖示)發出之光束的峰值波長均大於860nm，一較佳範圍為峰值波長大於890nm，且一更佳範圍為峰值波長大於950nm。圖2顯示光遮斷器的發光元件及受光元件的光譜分佈曲線。如圖2所示，發光元件可為使用GaAs材料的紅外光LED，其發光峰值波長約為950nm。再者，圖3顯示影像感測器的光學響應圖，如圖3所示，當紅光入射至影像感測器的入射光波長大於860nm，量子效率已降至16%以下，當紅光入射光波長大於950nm，量子效率可進一步降至6%以下，亦即影像感測器對紅光波長的入射光幾乎無法感應。同理，若將影像感測器對紅外光(IR)的光學響應在峰值時的量子效率定為100%，波長越高的紅外光(IR)入射至影像感測器的量子效率會相對於峰值越往下降，例如降至15%、10%甚至5%以下，而越不容易產生鬼影。因此，本發明一實施例設計使第一光遮斷器16及第二光遮斷器18發出之光束的峰值波長位於影像感測器感應紅外光(IR)的一感應波長範圍外，若影像感測器對紅外光(IR)的光學響應在峰值時的量子效率定為100%，於本實施例中影像感測器的感應波長範圍可為對應大於15%的量子效率的波長範圍，於另一實施例中感應波長範圍可為對應大於10%的量子效率的波長範圍，於又一實施例中感應波長範圍可為對應大於5%的量子效率的波長範圍。當遮斷器發出之光束的峰值波長位於影像感測器感應紅外光(IR)的一感應波長範圍外，影像感測器幾乎無法對第一光遮斷器16及第二光遮斷器18發出的光線成像而可大幅降低或避免鬼影產生。 FIG1 is a schematic diagram of a zoom lens according to an embodiment of the present invention. As shown in FIG1 , the zoom lens 10 has a zooming lens group 12, a focusing lens group 14, a first light blocker 16, and a second light blocker 18. In a typical light blocker, there are a light emitting element and a light receiving element that can form a light path, and there is an air gap between the light emitting element and the light receiving element. If there is no object blocking the gap, the light emitted by the light emitting element will directly illuminate the light receiving element; on the contrary, if there is an object blocking the light in the gap, the light receiving element will not be illuminated by light and the output state will change. Therefore, the first light interrupter 16 can confirm the position of the zoom lens group 12 by detecting the change between the light-shielding state and the non-light-shielding state, and the second light interrupter 18 can confirm the position of the focus lens group 14 by detecting the change between the light-shielding state and the non-light-shielding state. In this embodiment, the peak wavelength of the light beam emitted by the light-emitting element (not shown) of the first light interrupter 16 and the second light interrupter 18 is greater than 860nm, a preferred range is a peak wavelength greater than 890nm, and a more preferred range is a peak wavelength greater than 950nm. FIG. 2 shows the spectral distribution curve of the light-emitting element and the light-receiving element of the light interrupter. As shown in FIG. 2, the light-emitting element can be an infrared light LED using GaAs material, and its light emission peak wavelength is about 950nm. Furthermore, Figure 3 shows the optical response diagram of the image sensor. As shown in Figure 3, when the wavelength of the incident red light incident on the image sensor is greater than 860nm, the quantum efficiency has dropped to below 16%. When the wavelength of the incident red light is greater than 950nm, the quantum efficiency can be further reduced to below 6%, that is, the image sensor is almost insensitive to incident light of red wavelength. Similarly, if the quantum efficiency of the image sensor's optical response to infrared light (IR) at the peak is set to 100%, the higher the wavelength of infrared light (IR) incident on the image sensor, the lower the quantum efficiency will be relative to the peak, for example, it will drop to 15%, 10% or even below 5%, and it will be less likely to produce ghost images. Therefore, one embodiment of the present invention is designed so that the peak wavelength of the light beam emitted by the first light blocker 16 and the second light blocker 18 is outside a sensitive wavelength range of the image sensor sensing infrared light (IR). If the quantum efficiency of the optical response of the image sensor to infrared light (IR) at the peak is set to 100%, in this embodiment, the sensitive wavelength range of the image sensor can be a wavelength range corresponding to a quantum efficiency greater than 15%, in another embodiment, the sensitive wavelength range can be a wavelength range corresponding to a quantum efficiency greater than 10%, and in yet another embodiment, the sensitive wavelength range can be a wavelength range corresponding to a quantum efficiency greater than 5%. When the peak wavelength of the light beam emitted by the blocker is outside the wavelength range of infrared (IR) light sensed by the image sensor, the image sensor is almost unable to form an image of the light emitted by the first light blocker 16 and the second light blocker 18, thereby significantly reducing or avoiding the generation of ghost images.

本發明實施例的變焦鏡頭的組成並不限定，如圖1所示的可動鏡組(例如變焦鏡組或對焦鏡組)亦可搭配其他不限數量的固定鏡組。如圖4所示，一取像裝置1可包含變焦鏡頭20、配置在變焦鏡頭20像側的濾光片3、及產生影像的影像感測器4、變焦鏡頭20可由第一鏡組G1、第二鏡組G2、第三鏡組G3、第四鏡組G4及第五鏡組G5所構成，第二鏡組G2及第四鏡組G4為可動鏡組，且其餘鏡組為固定鏡組。第二鏡組G2例如可為一變焦鏡組，且第四鏡組G4例如可為一對焦鏡組。影像感測器4例如可為感光耦合元件(CCD)或互補性氧化金屬半導體(CMOS)。圖5為圖4的變焦鏡頭實施例的剖面示意圖。如圖5所示，變焦鏡頭20的第二鏡組G2(變焦鏡組)沿著光軸2方向運動以進行變焦操作，第四鏡組G4(對焦鏡組)沿著光軸2方向運動以進行對焦操作，箭頭X的方向為變焦鏡組G2從廣角端到望遠端移動的方向，箭頭-X的方向為變焦鏡組G2從望遠端到廣角端移動的方向。驅動機件22沿著光軸2的方向驅動變焦鏡組G2，且驅動機件24沿著光軸2方向驅動對焦鏡組G4。驅動機件22及驅動機件24例如可為步進馬達、音圈馬達及壓電元件等而不限定。光遮斷器16可藉由偵測設在變焦鏡組G2的遮光部222所產生的遮光狀態和無遮光狀態，確認變焦鏡組G2的位置，且光遮斷器18可藉由偵測設在對焦鏡組G4的遮光部242所產生的遮光狀態和無遮光狀態，以確認對焦鏡組G4的位置。 The composition of the zoom lens of the embodiment of the present invention is not limited. The movable lens group (such as a zoom lens group or a focus lens group) shown in FIG1 can also be matched with an unlimited number of other fixed lens groups. As shown in FIG4, an imaging device 1 can include a zoom lens 20, a filter 3 disposed on the image side of the zoom lens 20, and an image sensor 4 for generating an image. The zoom lens 20 can be composed of a first lens group G1, a second lens group G2, a third lens group G3, a fourth lens group G4, and a fifth lens group G5. The second lens group G2 and the fourth lens group G4 are movable lens groups, and the remaining lens groups are fixed lens groups. The second lens group G2 can be, for example, a zoom lens group, and the fourth lens group G4 can be, for example, a focus lens group. The image sensor 4 may be, for example, a charge coupled device (CCD) or a complementary metal oxide semiconductor (CMOS). FIG. 5 is a cross-sectional schematic diagram of the zoom lens embodiment of FIG. 4 . As shown in FIG. 5 , the second lens group G2 (zoom lens group) of the zoom lens 20 moves along the direction of the optical axis 2 to perform a zoom operation, and the fourth lens group G4 (focus lens group) moves along the direction of the optical axis 2 to perform a focusing operation. The direction of the arrow X is the direction in which the zoom lens group G2 moves from the wide-angle end to the telephoto end, and the direction of the arrow -X is the direction in which the zoom lens group G2 moves from the telephoto end to the wide-angle end. The drive mechanism 22 drives the zoom lens group G2 along the direction of the optical axis 2, and the drive mechanism 24 drives the focus lens group G4 along the direction of the optical axis 2. The driving mechanism 22 and the driving mechanism 24 may be, for example, a stepping motor, a voice coil motor, a piezoelectric element, etc., but are not limited thereto. The light interrupter 16 can confirm the position of the zoom lens group G2 by detecting the light-shielding state and the non-light-shielding state generated by the light-shielding portion 222 provided in the zoom lens group G2, and the light interrupter 18 can confirm the position of the focusing lens group G4 by detecting the light-shielding state and the non-light-shielding state generated by the light-shielding portion 242 provided in the focusing lens group G4.

再者，依本發明一實施例的設計，第一光遮斷器16及第二光遮斷器18可分別具有彼此獨立運作而非共用的電路，舉例而言，第一光遮斷器16及第二光遮斷器18可具有各自獨立的陽極/陰極結構，使第一光遮斷器16及第二光遮斷器18可單獨斷電或開啟。藉由此一設計，第一光遮斷器16及第二光遮斷器18均可單獨控制以進行避免鬼影產生的操作，舉例而言，當變焦鏡組12進行變焦操作(zooming)時第一光遮斷器16可作動以確認變焦鏡組12位置，且此時第二光遮斷器18可關閉；另一方面，當對焦鏡組14進行對焦操作(focusing)時第二光遮斷器18可作動以確認變對焦鏡組14位置，且此時第一光遮斷器16可關閉。藉由第一光遮斷器16與第二光遮斷器18的交替作動可有效減少或避免鬼影產生。藉由上述實施例的設計，因可分別獨立運作第一光遮斷器16及第二光遮斷器18，故可交替作動第一光遮斷器16與第二光遮斷器18、或可視變焦鏡頭的實際調焦方式決定第一光遮斷器16與第二光遮斷器18的開閉時序，藉以有效減少或完全避免鬼影產生。 Furthermore, according to the design of an embodiment of the present invention, the first photointerrupter 16 and the second photointerrupter 18 may have circuits that operate independently of each other rather than sharing a common circuit. For example, the first photointerrupter 16 and the second photointerrupter 18 may have independent anode/cathode structures, so that the first photointerrupter 16 and the second photointerrupter 18 can be powered off or on separately. With this design, the first light blocker 16 and the second light blocker 18 can be controlled individually to perform operations to avoid ghost images. For example, when the zoom lens group 12 performs a zooming operation (zooming), the first light blocker 16 can be activated to confirm the position of the zoom lens group 12, and the second light blocker 18 can be closed at this time. On the other hand, when the focus lens group 14 performs a focusing operation (focusing), the second light blocker 18 can be activated to confirm the position of the focus lens group 14, and the first light blocker 16 can be closed at this time. The alternating operation of the first light blocker 16 and the second light blocker 18 can effectively reduce or avoid the generation of ghost images. By the design of the above embodiment, since the first light blocker 16 and the second light blocker 18 can be operated independently, the first light blocker 16 and the second light blocker 18 can be operated alternately, or the actual focusing method of the visual zoom lens determines the opening and closing timing of the first light blocker 16 and the second light blocker 18, thereby effectively reducing or completely avoiding the generation of ghost images.

雖然本發明已以較佳實施例揭露如上，然其並非用以限定本發明，任何熟習此技藝者，在不脫離本發明之精神和範圍內，當可作些許之更動與潤飾，因此本發明之保護範圍當視後附之申請專利範圍所界定者為準。另外，本發明的任一實施例或申請專利範圍不須達成本發明所揭露之全部目的或優點或特點。此外，摘要部分和標題僅是用來輔助專利檔搜尋之用，並非用來限制本發明之權利範圍。 Although the present invention has been disclosed above in terms of preferred embodiments, they are not intended to limit the present invention. Anyone skilled in the art may make some modifications and modifications without departing from the spirit and scope of the present invention. Therefore, the present invention The scope of protection shall be subject to the scope of the patent application attached. In addition, any embodiment or patentable scope of the present invention does not necessarily achieve all the purposes, advantages or features disclosed in the present invention. In addition, the abstract section and title are only used to assist in searching patent documents and are not intended to limit the scope of the invention.

10‧‧‧變焦鏡頭 10‧‧‧zoom lens

12‧‧‧變焦鏡組 12. Zoom lens set

14‧‧‧對焦鏡組 14‧‧‧Focus lens group

16‧‧‧第一光遮斷器 16. First photointerrupter

18‧‧‧第二光遮斷器 18. Second photointerrupter

Claims

一種變焦鏡頭，包含：一變焦鏡組和一對焦鏡組；一第一光遮斷器，用以偵測該變焦鏡組的位置；一第一電路，用以開啟或關閉該第一光遮斷器；一第二光遮斷器，用以偵測該對焦鏡組的位置；以及一第二電路，用以開啟或關閉該第二光遮斷器，其中該第一電路與該第二電路設為分別獨立運作，並設置為該第二光遮斷器在該第一光遮斷器作動時關閉，且設置為該第一光遮斷器在該第二光遮斷器作動時關閉，藉以減少或避免鬼影產生。 A zoom lens, including: a zoom lens group and a focusing lens group; a first photointerrupter for detecting the position of the zoom lens group; a first circuit for turning on or off the first photointerrupter interrupter; a second photointerrupter for detecting the position of the focusing lens group; and a second circuit for turning on or off the second photointerrupter, wherein the first circuit and the second The circuit is configured to operate independently, and the second photointerrupter is configured to be closed when the first photointerrupter is activated, and the first photointerrupter is configured to be closed when the second photointerrupter is activated. , to reduce or avoid ghosting.

如申請專利範圍第1項所述之變焦鏡頭，其中該第一光遮斷器發出的光束的峰值波長大於860nm。 For the zoom lens described in item 1 of the patent application, the peak wavelength of the light beam emitted by the first photointerrupter is greater than 860 nm.

一種變焦鏡頭，包含：一變焦鏡組和一對焦鏡組，該變焦鏡組和該對焦鏡組可於一光軸上移動以分別進行變焦及對焦操作；一第一光遮斷器，用以偵測該變焦鏡組的位置；以及一第二光遮斷器，用以偵測該對焦鏡組的位置，其中該第一光遮斷器及該第二光遮斷器設置為該第二光遮斷器在該第一光遮斷器作動時關閉，且設置為該第一光遮斷器在該第二光遮斷器作動時關閉，藉以減少或避免鬼影產生。 A zoom lens comprises: a zoom lens group and a focus lens group, the zoom lens group and the focus lens group can move on an optical axis to perform zoom and focus operations respectively; a first light interrupter for detecting the position of the zoom lens group; and a second light interrupter for detecting the position of the focus lens group, wherein the first light interrupter and the second light interrupter are arranged so that the second light interrupter is closed when the first light interrupter is actuated, and the first light interrupter is arranged so that the second light interrupter is closed when the second light interrupter is actuated, so as to reduce or avoid the generation of ghost images.

如申請專利範圍第3項所述之變焦鏡頭，其中該第一光遮斷器發出的光束的峰值波長大於860nm。 A zoom lens as described in Item 3 of the patent application, wherein the peak wavelength of the light beam emitted by the first light interrupter is greater than 860nm.

如申請專利範圍第2或4項所述之變焦鏡頭，更包含至少一固定鏡組。 The zoom lens described in Item 2 or 4 of the patent application further includes at least one fixed lens group.

如申請專利範圍第2或4項所述之變焦鏡頭，其中該光束的峰值波長大於890nm。 A zoom lens as described in item 2 or 4 of the patent application, wherein the peak wavelength of the light beam is greater than 890nm.

如申請專利範圍第2或4項所述之變焦鏡頭，其中該光束的峰值波長大於950nm。 A zoom lens as described in item 2 or 4 of the patent application, wherein the peak wavelength of the light beam is greater than 950nm.

如申請專利範圍第1-4項中任一項所述之變焦鏡頭，其中該變焦鏡組及該對焦鏡組分別設有一遮光部，且各該光遮斷器偵測該遮光部產生的遮光狀態和無遮光狀態以確認該變焦鏡組及該對焦鏡組的位置。 The zoom lens as described in any one of items 1 to 4 of the patent application, wherein the zoom lens group and the focus lens group are respectively provided with a light shielding portion, and each photointerrupter detects the light blocking generated by the light shielding portion. status and unblocked status to confirm the position of the zoom lens group and the focusing lens group.