J. H. Chang, Y. Yoo, T. –K. Song, and J. Lee, “Method for producing intravascular ultrasonic transducers and structure thereof,” EU Patent #3089479, 2019.

J. H. Chang and J. Lee, “Intravascular ultrasound transducer assembly for occlusion tunneling and manufacturing method thereof,” Korea Patent #10-1974484, 2019.

J. H. Chang and K. Kim, “System for removing background noise of photoacoustic imaging,” Korea Patent # 10-1956308, 2019.

J. H. Chang and H. Kim, “Controlling method of light energy penetration depth using ultrasonic energy and apparatus thereof,” Korea Patent #10-1956446, 2019.

Y. Yoo, T. –K. Song, J. H. Chang, J. Cho, and J. H. Park, “Method for generating synthetic image and ultrasonic imaging apparatus using same,” US Patent #10,101,449, 2019

J. H. Chang, J. H. Cha, and J. Jang, “Ultrasound transducer using integrally formed flexible printed circuit board and manufacturing method therefor,” Korea Patent #10-1839956, 2018.

T. –K. Song, Y. M. Yoo, J. H. Chang, and J. Song, “Ultrasound imaging system of generating a HIFU focus image and method of generating it,” China Patent #ZL201280047734.4, 2017.

K. -Y. Ju, J. Kang, J. H. Chang, and J. -K. Lee, “Photoacoustic image agent comprising a melanin nanoparticle,” Korea Patent #10-1731140, 2017.

J. H. Chang, J. Kang, T. –K. Song, and Y. M. Yoo, “Method for discriminating between background and tissue of interest, and method and apparatus for generating photoacoustic images for detecting calcified tissue,” US Patent # 9,478,023, 2016.

H. Kim, J. H. Chang, H. Moon, and H. Lee, “System and method for diagnosing using photoacoustic/ultrasound contrast agent,” Korea Patent #10-1665633, 2016.

J. H. Chang and T. –K. Song, “Concave array ultrasound transducers for ophthalmic imaging,” China Patent # 201180042789.1, 2016.

Y. M. Yoo, J. H. Kim, K. C. Kim, J. H. Chang, and T. –K. Song, “Ultrasonic image quality improving method and ultrasonic imaging apparatus using the same,” Korea Patent #10-1652728, 2016.

T. –K. Song, S. Bae, and J. H. Chang, “Estimation method and system for shear wave speed and lesion diagnosis method and system in the tissue using the same,” Korea Patent #10-1646623, 2016.

J. H. Chang, J. H. Song, Y. M. Yoo, and T. –K. Song, “Method and device for removing an HIFU interference signal,” China Patent #2012 8 0059157.0, 2016.

Y. M. Yoo, T. –K. Song, J. H. Chang, J. Cho, and J. H. Park, “Method and apparatus for motion compensation in ultrasound synthetic aperture imaging,” US Patent #9,299,174, 2016.

J. H. Chang, T. –K. Song, Y. M. Yoo, and J. Kang, “Apparatus and method of producing photoacoustic images,” Korea Patent #10-1601171, 2016.

Y. M. Yoo, M. Kim, J. Kang, J. H. Chang, and T. –K. Song, “Apparatus and method for obtaining photoacoustic image using motion compensation,” Korea Patent #10-1581689, 2015.

J. H. Chang, T. –K. Song, Y. M. Yoo, and J. S. Lee, “Method for manufacturing intravascular ultrasound transducers and intravascular ultrasound transducer structure thereby,” Korea Patent #10-1568682, 2015.

J. H. Chang and J. S. Lee, “Method for manufacturing intravascular ultrasound transducers and intravascular ultrasound transducer structure thereby,” Korea Patent # 10-1560558, 2015.

Y. M. Yoo, W. Y. Lee, C. H. Yoon, J. H. Chang, and T. –K. Song, “Apparatus and method for pulse compression of coded excitation in medical ultrasound imaging,” Korea Patent # 10-1550671, 2015

J. H. Chang, J. H. Song, T. –K. Song, Y. M. Yoo, and S. Bae, “Apparatus and method for generating elastography using sheare wave,” Korea Patent # 10-1542835, 2015.

Y. M. Yoo, Y. H. Lee, J. H. Chang, and T. –K. Song, “Image quality improving method and ultrasonic imaging apparatus using the same,” Korea Patent # 10-1542807, 2015.

Y. M. Yoo, J. Kang, M. Kim, J. H. Chang, and T. –K. Song, “Picture quality improvement method and system of ultrasonic medical image based on multiscale,” Korea Patent #10-1533968, 2015.

Y. M. Yoo, J. Ye, T. –K. Song, and J. H. Chang, “Lesion monitoring method and medical imaging system,” Korea Patent #10-1525433, 2015.

Y. M. Yoo, J. H. Park, J. H. Chang, and T. –K. Song, “Ultrasound Transducer, Ultrasound Medical Imaging System and 3D Ultrasound Image Generating Method,” Korea Patent #10-1511221, 2015.

J. H. Chang, C. H. Yoon, Y. M. Yoo, and T. –K. Song, “Display pixel based focusing method using quadrature sampling in photoacoustic imaging and apparatus thereof,” Korea Patent #10-1509447, 2015.

Y. Yoo, Y. H. Lee, J. H. Chang, and T. –K. Song, “A three-dimensional (3D) image representation method of an ultrasonic wave image,” Korea Patent #10-1499563, 2015.

Y. Yoo, C. H. Kim, J. H. Chang, and T. –K. Song, “Vein visualization method using estimated reflectance spectrums, guide apparatus for vascular access using the method thereof and user authentication apparatus using the method thereof,” Korea Patent #10-1494638, 2015.

J. H. Chang, H. Kim, Y. Yoo, and T. –K. Song, “Therapeutic and real-time image-guided and treatment monitoring method and apparatus for dermatological diseases,” Korea Patent #10-1480337, 2015.

H. Kim, H. Moon, T. –K. Song, J. H. Chang, and Y. Yoo, “Ultrasound contrast agent with nanoparticles including drug and method for preparing the same,” Korea Patent #10-1487088, 2015.

Y. Yoo, Y. Lee, C. Kim, J. H. Chang, T. –K. Song, and G. –D. Kim, “Dynamic range adjustment method using log average,” Korea Patent #10-1450800, 2014.

J. H. Chang, S. H. Kim, H. Cho, Y. Yoo, and T. –K. Song, “Multi beam former apparatus and method using polyphase interpolation filter,” Korea Patent #10-1442221, 2014.

Y. Yoo, J. H. Park, J. H. Chang, and T. –K. Song, “Synthetic aperture beamforming method and apparatus for interpolating time delay,” Korea Patent #10-1435979, 2014.

Y. Yoo, J. Yu, S. Yeu, J. H. Chang, and T. –K. Song, “Method and apparatus of producing functional flow images using plain wave,” Korea Patent #10-1433032, 2014.

Y. Yoo, S. Jin, J. Kang, J. H. Chang, and T. –K. Song, “Method for estimating speed of ultrasonic waves, method and apparatus for ultrasonic imaging using the estimated speed thereof,” Korea Patent #10-1393512, 2014.

J. H. Chang, T. –K. Song, Y. Yoo, and J. Kang, “System of controlling the operation of chips by host,” Korea Patent #10-1408267, 2014.

J. H. Chang, T. –K. Song, Y. Yoo, and D. Song, “Apparatus and method for adaptive dynamic quadrature demodulation,” Korea Patent #10-1363543, 2014.

J. H. Chang, J. Kang, T. –K. Song, and Y. Yoo, “Method and apparatus of differentiating between a background and a region of interest,” Korea Patent #10-1352769, 2014.

Y. Yoo, T. –K. Song, J. H. Chang, J. Cho, and J. H. Park, “Board for synthetic aperture beamforming apparatus,” Korea Patent #10-1298934, 2013.

B. –H. Kim, J. H. Chang, D. Kim, J. Song, T. –K. Song, Y. Yoo, and K. Cho, “Diagnosis system for diagnosing subject, medical image system for providing diagnosis image of subject and method for displaying diagnosis image of subject,” Korea Patent #10-1303626, 2013.

J. H. Chang, J. Song, Y. Yoo, and T. –K. Song, “Method and apparatus of cancelling residual HIFU interference,” Korea Patent #10-1334375, 2013.

J. H. Chang, J. S. You, Y. Yoo, and T. –K. Song, “Adaptive dynamic quadrature demodulation apparatus for ultrasound harmonic imaging and demodulation method thereof,” Korea Patent #10-1339683, 2013.

Y. Yoo, W. Y. Lee, J. H. Park, J. H. Chang, and T. –K. Song, “A synthetic aperture beamforming system of using phase rotation beamformers,” Korea Patent #10-1334381, 2013.

J. H. Chang, H. Song, J. H. Cha, J. S. Lee, Y. Yoo, and T. –K. Song, “Array transducer manufacturing method for ultrasonic waves image and ultrasonic wave image device using the same,” Korea Patent #10-1312310, 2013.

J. H. Chang, T. –K. Song, Y. Yoo, and Y. Lee, “Ultrasound signal processing method for removing HIFU signal, apparatus thereof,” Korea Patent #10-1312307, 2013.

Y. Yoo, T. –K. Song, J. H. Chang, and J. Song, “Ultrasound imaging system of generating a HIFU focus image and method of generating it,” Korea Patent #10-1317359, 2013.

Y. Yoo, T. –K. Song, J. H. Chang, and J. Song, “Apparatus and method for HIFU therapy capable of confirming focal spot of therapy signal,” Korea Patent #10-1312303, 2013.

Y. Yoo, J. Kang, J. H. Chang, and T. –K. Song, “Apparatus and method of forming beams adaptively in ultrasound imaging,” Korea Patent #10-1312309, 2013.

J. H. Chang, T. –K. Song, Y. Yoo, and J. S. You, “Method for processing ultrasound images using nonlinear property, apparatus thereof,” Korea Patent #10-1312312, 2013.

J. H. Chang, J. Kang, Y. Yoo, T. –K. Song, and S. Bae, “The sound speed correction method and apparatus based on lateral spatial frequency analysis,” Korea Patent #10-1298936, 2013.

Y. Yoo, J. Kang, J. H. Chang, and T. –K. Song, “Method and apparatus of producing ultrasound images and photoacoustic images,” Korea Patent #10-1298935, 2013.

J. H. Chang, T. –K. Song, Y. Yoo, and J. Kang, “Method of producing photoacoustic image for detecting calcification tissue and producing apparatus thereof,” Korea Patent #10-1287099, 2013.

J. H. Chang, T. –K. Song, Y. Yoo, and C. Yoon, “Method of synthesizing frequency image using the energy of each frequency band and apparatus thereof,” Korea Patent #10-1287098, 2013.

J. H. Chang, T. –K. Song, Y. Yoo, and C. Yoon, “Method of producing ultrasound images using orthogonal nonlinear codes and apparatus thereof,” Korea Patent #10-1282764, 2013.

Y. Yoo, T. –K. Song, J. H. Chang, J. Cho, and J. H. Park, “Method of forming a synthesized image and ultrasound imaging device using it,” Korea Patent #10-1253608, 2013.

Y. Yoo, T. –K. Song, J. H. Chang, J. Cho, and J. H. Park, “Synthetic aperture beamforming method of determining the number of synthesized beams referring to degree of motion and apparatus using it,” Korea Patent #10-1226903, 2013.

J. H. Chang and T. –K. Song, “Method of Producing Ultrasound Image using Concave Array,” Korea Patent #10-1126184 and PCT/KR2011/004951, 2012.

Y. Yoo, T. –K. Song, J. H. Chang, and J. Song, “Apparatus and method for HIFU therapy capable of confirming focal spot and evaluating therapy progress of therapy signal,” Korea Patent #10-1207309, 2012.

Y. Yoo, T. –K. Song, J. H. Chang, and J. Lee, “Method and apparatus of estimating ultrasound speed using amplitude of channel data,” Korea Patent #10-1214820, 2012.

Y. Yoo, T. –K. Song, J. H. Chang, J. Song, and H. Yoon, “Harmonic imaging apparatus of using nonlinear chirp signal and method thereof,” Korea Patent #10-1126182, 2012.

Y. Yoo, T. K. Song, J. H. Chang, and H. Seo, “Method and apparatus of estimating speed of ultra-sound using edge conspicuity,” Korea Patent #10-1098966, 2011.

D. –G. Paeng, H. Ameri, J. H. Chang, K. K. Shung, and M. Humayun, “High Frequency Ultrasound Imaging by Rotational Scanning of Angled Transducers,” PCT International Application #PCT/US2009/034643 (WO 2009/105616 A2), 2009.

J. S. Jeong, J. H. Chang, and K. K. Shung, “Ultrasonic Apparatus and Method for Real-time Simultaneous Therapy and Diagnosis,” US Patent Application Serial #12/407,580, 2009.

H. H. Kim, J. H. Chang, and K. K. Shung, “High Frequency Ultrasonic Convex Array Transducers and Tissue Imaging,” PCT International Application #PCT/US2008/077857, 2008.

J. H. Chang, “Server System and Method for Transmitting an Error Message to a Client System,” Korea Patent #10-0519016, 2005.

T. –K. Song and J. H. Chang, "Synthetic Aperture Focusing Method For Ultrasound Imaging Based On Planar Waves" US #6,736,780, 2004.