A beam splitter apparatus, comprising: a housing, provided with a light inlet; a connecting structure, disposed on a housing edge at the light inlet, wherein the connecting structure is configured to connect to an image side end of a lens barrel of an imaging lens module, so that the light inlet is opposite to an image side surface of an imaging lens group of the imaging lens module; and a beam splitter plate, disposed obliquely in the housing and in a transmission path of an imaging beam of a camera, comprising: a transmissive plate that is a light-transmitting plate-like structure; and a beam splitter film, supported on the transmissive plate and parallel to the transmissive plate, wherein the beam splitter film is configured to reflect visible light and transmit near-infrared light, or the beam splitter film is configured to reflect near-infrared light and transmit visible light, wherein a thickness of the transmissive plate satisfies that when the beam splitter plate is disposed obliquely in the transmission path of the imaging beam of the camera, transmission path lengths of visible light and near-infrared light in the imaging beam in the transmissive plate are both less than a projection length of the beam splitter film on an optical axis of the imaging beam, wherein the transmissive plate has a first surface and a second surface opposite to each other; and the beam splitter film is attached to the second surface, and wherein the beam splitter plate further comprises: a third antireflective film, attached to the first surface, wherein the third antireflective film is configured to increase transmittances of visible light and near-infrared light that are incident into the transmissive plate from the first surface. a housing, provided with a light inlet; a connecting structure, disposed on a housing edge at the light inlet, wherein the connecting structure is configured to connect to an image side end of a lens barrel of an imaging lens module, so that the light inlet is opposite to an image side surface of an imaging lens group of the imaging lens module; and a beam splitter plate, disposed obliquely in the housing and in a transmission path of an imaging beam of a camera, comprising: a transmissive plate that is a light-transmitting plate-like structure; and a beam splitter film, supported on the transmissive plate and parallel to the transmissive plate, wherein the beam splitter film is configured to reflect visible light and transmit near-infrared light, or the beam splitter film is configured to reflect near-infrared light and transmit visible light, wherein a thickness of the transmissive plate satisfies that when the beam splitter plate is disposed obliquely in the transmission path of the imaging beam of the camera, transmission path lengths of visible light and near-infrared light in the imaging beam in the transmissive plate are both less than a projection length of the beam splitter film on an optical axis of the imaging beam, wherein the transmissive plate has a first surface and a second surface opposite to each other; and the beam splitter film is attached to the second surface, and wherein the beam splitter plate further comprises: a third antireflective film, attached to the first surface, wherein the third antireflective film is configured to increase transmittances of visible light and near-infrared light that are incident into the transmissive plate from the first surface. a transmissive plate that is a light-transmitting plate-like structure; and a beam splitter film, supported on the transmissive plate and parallel to the transmissive plate, wherein the beam splitter film is configured to reflect visible light and transmit near-infrared light, or the beam splitter film is configured to reflect near-infrared light and transmit visible light, wherein a thickness of the transmissive plate satisfies that when the beam splitter plate is disposed obliquely in the transmission path of the imaging beam of the camera, transmission path lengths of visible light and near-infrared light in the imaging beam in the transmissive plate are both less than a projection length of the beam splitter film on an optical axis of the imaging beam, wherein the transmissive plate has a first surface and a second surface opposite to each other; and the beam splitter film is attached to the second surface, and wherein the beam splitter plate further comprises: a third antireflective film, attached to the first surface, wherein the third antireflective film is configured to increase transmittances of visible light and near-infrared light that are incident into the transmissive plate from the first surface.